Emperor Taizong's campaign against Goguryeo
Encyclopedia
The First Goguryeo–Tang War started when Emperor Taizong of Tang
(r. 626-649), the second emperor of Chinese
dynasty Tang Dynasty
, asserting that a campaign against Goguryeo
was necessary to protect Tang's ally Silla
, as well as to punish Goguryeo's Dae Mangniji (대막리지, 大莫離支, Generalissimo
) Yeon Gaesomun
for his killing of Goguryeo's King Yeongnyu
, launched a major campaign against Goguryeo in 644, commanded by himself with the assistance of the generals Li Shiji
, Li Daozong
, and Zhangsun Wuji
.
In 645, after defeating the main Goguryeo army, Emperor Taizong appeared poised to march on Goguryeo's capital Pyongyang
and conquer Goguryeo, but became bogged down by the strong defenses put up by the defender of Ansi (安市, in modern Anshan, Liaoning
) -- whose name is lost to history but is traditionally believed to be Yang Manchun
-- and was unable to proceed further. Thereafter, for the rest of his reign, Emperor Taizong limited his attack on Goguryeo to harassment raids, and would not again launch a major attack. After Tang and Huige destroyed Xueyantuo
in 646, Emperor Taizong started to built up his army and navy in anticipation for another major campaign in 649, but Emperor Taizong died that same year, stalling the campaign. The Tang Dynasty failed to conquer Goguryeo until 668. In 668, Tang destroyed Goguryeo in alliance with Silla, during the reign of Emperor Taizong's son Emperor Gaozong
.
against Goguryeo
during the reign of Emperor Yang of Sui
had been one of the major reasons for the downfall of Tang Dynasty
's predecessor, Sui Dynasty
. After Tang was founded in 618, Tang's founder Emperor Gaozu
made peace with Goguryeo's King Yeongnyu
, with the states making an exchange of prisoners of war in 622 and with King Yeongnyu subsequently, in 624, accepting Tang era name and the Tang-created titles of Prince of Liaodong and King of Goguryeo. (At the same time, Emperor Gaozu also created the kings of Goguryeo's two southern neighbors princely titles --Baekje
's King Mu
as the Prince of Daifang and Silla
's King Jinpyeong
as the Prince of Lelang.)
In 626, Emperor Gaozu's son Li Shimin
the Prince of Qin, locked in an intense rivalry with his older brother Li Jiancheng
the Crown Prince
, ambushed and killed Li Jiancheng and another brother who supported Li Jiancheng, Li Yuanji
the Prince of Qi, at the Incident at Xuanwu Gate
. He then effectively forced Emperor Gaozu to first create him crown prince and then pass the throne to him (as Emperor Taizong). For most of Emperor Taizong's reign, the relationship between Tang and Goguryeo appeared to be largely friendly, with Emperor Taizong trying to assert more of an overlord role over the dispute between Goguryeo and its rivals Baekje and Silla. For example, soon after Emperor Taizong took the throne in 626, he sent his official Zhu Zishe (朱子奢) to rebuke the three states for attacking each other. In 631, Emperor Taizong sent emissaries to Goguryeo to rebury the Sui war dead, which King Yeongnyu permitted.
In 641, Emperor Taizong sent the official Chen Dade (陳大德) as an emissary to Goguryeo, and on the trip, Chen traveled throughout Goguryeo and met a large number of former Sui soldiers who had settled in Goguryeo, and upon return to the Tang capital Chang'an
, he reported his findings to Emperor Taizong. Emperor Taizong began contemplating attacking Goguryeo, but then dismissed his own idea, stating that he did not want to trouble the people in the eastern part of his empire.
In 642, however, an event that would trigger Emperor Taizong to rethink his position occurred. King Yeongnyu had been considering to kill his general Yeon Gaesomun
, believing Yeon to be violent and criminal. Yeon, after receiving such news, set a trap for the king and a number of officials under guise of a banquet and view of troops, and then killed both the officials and the king. He supported King Yeongnyu's brother Go Jang
as king (as King Bojang). Yeon himself took the title of Dae Mangniji (大莫離支, regent) and had the actual control of the government and the military. When the news reached Tang, the official Pei Xingzhuang (裴行莊) suggested attacking Goguryeo, which Emperor Taizong again declined, stating that he mourned King Yeongnyu but that it would be inappropriate to attack Goguryeo in light of King Yeongnyu's death. However, in 643, he again considered military options, but initially considered only ordering the Khitan
and the Mohe to harass Goguryeo. Emperor Taizong's brother-in-law, the chancellor Zhangsun Wuji
opposed this and suggested instead assuring Yeon with offers of peace and then to catch him offguard. Emperor Taizong agreed, and affirmed King Bojang's ascension by creating him the Prince of Liaodong and King of Goguryeo, along with the honorific title of Shang Zhuguo (上柱國).
Later in 643, Silla's Queen Seondeok
submitted a report claiming that her state was under heavy attack by Baekje, allied with Goguryeo. She requested aid from Tang. Emperor Taizong sent the official Xiangli Xuanjiang (相里玄獎) to Goguryeo to order both it and Baekje to stop attacking Silla. When Xiangli arrived in the Goguryeo capital Pyongyang
, Yeon, who was attacking Silla at that time, returned to Pyongyang to meet with Xiangli, but refused to follow Emperor Taizong's order. When Xiangli returned to Chang'an and reported this to Emperor Taizong, Emperor Taizong resolved to attack Goguryeo, stating:
The general Li Shiji
was particularly supportive of the plan to attack Goguryeo, and Emperor Taizong decided to prepare for such a campaign, notwithstanding the opposition of Chu Suiliang
.
, Jiangxi
), Rao (饒州, roughly modern Shangrao
, Jiangxi
), and Jiang (江州, roughly modern Jiujiang
, Jiangxi
) to build some 400 supply ships for the campaign. He also had the commandant at Ying Prefecture (營州, roughly modern Zhaoyang, Liaoning
) command the troops from Ying and You (幽州, roughly modern Beijing
) prefectures, as well as troops from Khitan
, Xi
, and Mohe tribes loyal to Tang to make exploratory attacks in the Liaodong region, to test what Goguryeo's responses would be. Apparently to try to ward off the attack, Yeon Gaesomun sent emissaries to offer tributes of platinum. At Chu Suiliang's suggestion, Emperor Taizong rejected the platinum and further accused the emissaries of being loyal not to their king (the deceased King Yeongnyu) but to the regicide (i.e., Yeon); he put them under arrest. In winter 644, he left Chang'an and began his slow advance to the frontier, initially taking most of his officials as well as his crown prince
Li Zhi
with him, leaving the chancellor Fang Xuanling
and the general Li Daliang (李大亮) in charge of the capital. He headed first for the eastern capital Luoyang
, where he stayed several months in further preparation.
Around the new year 645, Emperor Taizong issued orders for Zhang Liang
to take some 43,000 soldiers, in 500 ships launching from Lai Prefecture (萊州, roughly modern Laizhou
, Shandong
), to advance across the Yellow Sea
heading toward Pyongyang; and for Li Shiji to command some 60,000 soldiers to head toward Liaodong on land. Emperor Taizong, confident of success, issued an edict that stated, among other things:
In spring 645, Emperor Taizong departed Luoyang, against the advice of the retired general Yuchi Jingde
, who was concerned that a rebellion similar to that Yang Xuangan
started against Emperor Yang in 613 during one of Emperor Yang's Goguryeo campaigns would develop. He left another chancellor, Xiao Yu
, in charge of Luoyang. Once he reached Ding Prefecture (定州, roughly modern Baoding
, Hebei
), he left Li Zhi there to be in charge of logistics, assisted by Gao Shilian
, Liu Ji
, Ma Zhou
, Zhang Xingcheng
, and Gao Jifu
. He continued proceeding, with Zhangsun Wuji, Cen Wenben
, and Yang Shidao
accompanying him. (Cen would die during the campaign.)
Meanwhile, Li Shiji and his deputy, Li Daozong
the Prince of Jiangxia (Emperor Taizong's cousin) had, in advance of Emperor Taizong, surprised Goguryeo forces by crossing the Liao River
. By summer 645, they had captured Gaemo (蓋牟, in modern Fushun
, Liaoning
). Meanwhile, Zhang Liang had crossed the Bohai Sea
and captured Bisa (卑沙, in modern Jinzhou
, Dalian
, Liaoning
) and sent his forward vessels to the mouth of the Yalu River
to try to intimidate Goguryeo forces, but was not heading toward Pyongyang as initially ordered by Emperor Taizong. Soon, Li Shiji and Li Daozong put the Goguryeo city of Yodong/Liaodong (遼東, in modern Liaoyang
, Liaoning
) -- a city that Emperor Yang had sieged multiple times but was unable to capture—under siege, and after Emperor Taizong arrived himself, Liaodong fell, and another key city, Baegam (白巖, also in modern Liaoyang) surrendered. Emperor Taizong next marched on Ansi.
: Gao Yanshou) and Go Hyezin (高惠真, pinyin: Gao Huizhen) put together an army of Goguryeo troops, as well as Mohe tribes allied with Goguryeo, totalling 150,000 men, and headed toward Ansi, intending to relieve it. When Emperor Taizong heard of the impending arrival of the Goguryeo army, he told his officials:
Meanwhile, a senior, experienced Goguryeo officer advised Go Yeonsu:
Go Yeonsu did not accept and continued to proceed to the vicinity of Ansi. Emperor Taizong, in order to further entice him to battle, sent the ethnically Turkic (Ch. Tujue) general Ashina She'er (阿史那社爾) to lead 1,000 Tujue cavalry soldiers forward, and once the Tujue soldiers engaged the Goguryeo forces, they pretended to flee. The Goguryeo forces gave chase and arrived at Ansi.
Emperor Taizong and his generals discussed the strategies, and they ascended the hills to discuss where troops could be hidden and where attacks could be made. Meanwhile, Li Daozong suggested that given that Go Yeonsu and Go Hyezin had this massive of an army, Pyongyang must be poorly defended, and he wanted to personally take 5,000 soldiers to make a surprise attack on Pyongyang, hoping to capture it. Emperor Taizong did not act on Li Daozong's proposal, but instead send a messenger to Go Yeonsu to state:
Go Yeonsu, believing that Emperor Taizong had no further intention to attack, relaxed in his preparations. Meanwhile, Emperor Taizong had Li Shiji take 15,000 soldiers and set up his camp on a hill to the west of the Goguryeo camp, and Zhangsun Wuji take 11,000 soldiers and position himself in a canyon north of the Goguryeo camp. Emperor Taizong himself took 4,000 soldiers and took up position on a hill north of the Goguryeo camp. The next day, July 20, 645, when Go Yeonsu noticed Emperor Taizong's camp to the north, he ordered an attack. As he did, Zhangsun made a surprise attack, and Emperor Taizong also attacked. The Goguryeo forces collapsed, and 20,000 men were killed. Go Yeonsu reorganized his troops and tried to defend his position, but Tang forces had him surrounded, and Zhangsun further destroyed the bridges to prevent a retreat. Two days later, Go Yeonsu and Go Hyezin surrendered with 36,800 men. Emperor Taizong said to them:
Emperor Taizong took 3,500 senior Goguryeo officers, conferred Tang titles on them, and had them sent to Tang proper. He released the other Goguryeo soldiers and sent them back to Pyongyang, but massacred the captured Mohe soldiers—some 3,300. In commemoration of his victory, Emperor Taizong named the location of the battle Mount Zhubi (駐驆山—i.e., "the mount where the imperial horse was").
After the Battle of Mount Zhubi, Yeon Gaesomun sent emissaries to Xueyantuo
's Zhenzhu Khan
Yi'nan, through Mohe intermediaries, to request that he attack Tang, offering to give him great tributes if he would do so. Yi'nan, in awe of Tang power, refused.
(The name of the defending general of Ansi has been lost to history, but is traditionally rendered in Korean popular accounts as Yang Manchun
, even though some Korean historical sources indicated that the name was lost.)
Li Shiji disagreed, however, arguing that as Geonan was to Ansi's south and that the main Tang food supply was coming from Liaodong, that if he attacked Geonan first, the defenders of Ansi would try to cut his supply lines. Emperor Taizong agreed, and Li Shiji began to siege Ansi.
When Emperor Taizong and Li Shiji arrived at Ansi, it was said that the Ansi defenders, upon seeing the banner of the Tang emperor, began to yell insults from the walls. Emperor Taizong was insulted, and Li Shiji received permission to slaughter the city's male inhabitants when it fell—which led to the Ansi defenders fighting even harder. Li Shiji was unable to capture the city for some time. Go Yeonsu and Go Hyezin, who had by now accepted Tang titles, suggested:
Some other officials also suggested:
Emperor Taizong was inclined to accept these proposals, but Zhangsun opposed, stating:
Emperor Taizong agreed with Zhangsun and did not head toward Ogol.
As the siege continued, on an occasion, when Emperor Taizong heard the sounds of chickens and pigs coming out of the city, he opined to Li Shiji that it must be that the Goguryeo defenders were preparing an assault and killing animals beforehand to feast on them. Li Shiji therefore prepared for a night assault, which came that night. Emperor Taizong himself led soldiers to repel the assault, and the Goguryeo forces withdrew within the city again.
Meanwhile, Li Daozong was building a dirt mound to the southeast of the city to use as an attack mechanism, and in response, the Ansi defenders added to the height of the wall to the southeast. This process continued for 60 days, and eventually, the dirt mound got so high that from it, one could easily see inside the city. Li Daozong had his officer Fu Fu'ai (傅伏愛) take position on the dirt mound. Suddenly, the mound had a partial collapse and fell onto the city walls, and the walls collapsed as well. At this moment, Fu, for reasons unexplained in history, left his position, and the Goguryeo forces took the opportunity to attack and capture the dirt mound, and instead used it as part of the defensive bulwarks. Emperor Taizong, in anger, executed Fu in public and ordered a heavy assault on the dirt mound, but could not capture it within three days. Li Daozong bared his feet and begged punishment, but Emperor Taizong pardoned him.
Meanwhile, winter was approaching, and the grass was drying up. Also, the food supplies were running out. On October 13, 645, Emperor Taizong ordered a withdrawal. He gave a demonstration ceremony next to Ansi before withdrawing.
As the army was crossing the mouth of Liao River, it was trapped by the marshes near the Liao for some time, requiring Zhangsun to command 10,000 men to carry out a project to fill the marshes in to allow the main army to withdraw. As weather was getting increasingly cold at the time, a number of Tang soldiers froze to death.
In all, according to both the medieval Chinese historical source Zizhi Tongjian
and the Korean historical source Samguk Sagi
, 70,000 Goguryeo people were forcibly moved to Tang territory. Some 40,000 Goguryeo soldiers were killed. According to the Zizhi Tongjian, the Tang forces lost approximately 2,000 men and 70-80% of their horses. However, modern Korean historians doubt the truth of the these records for various reasons. These scholars point to the retreat route of Chinese army, Taizong's acts in withdrawal, and casualties size of Chinese army, which described to Korean damage was a large figure compared with opposing force, and even scaled-down their harmed size.
Emperor Taizong regretted launching the campaign, and sighed, "If Wei Zheng
were still alive, he would not let me launch his campaign." He sent messengers to offer sacrifices to Wei, who had died in 643, and reerected a monument that he had previously built for Wei but which he had destroyed later in 643 after he wrongly believed that the deceased Wei had been in complicity with Hou Junji
and Du Zhenglun
. He also summoned Wei's wife and children to his presence and awarded them. Due to complications of his injury, he remained in Bing Prefecture (并州, roughly modern Taiyuan
, Shanxi
) for several months, before returning to Chang'an, and further transferred a substantial portion of his responsibilities to Li Zhi.
In 647, Emperor Taizong, after discussions with his officials, who pointed out that the 645 campaign, while unsuccessful, had caused Goguryeo to fall into famine, accepted their proposal of sending relatively small forces to harass Goguryeo's border region to prevent Goguryeo farmers from farming and therefore to create further food supply issues for Goguryeo. He therefore had Niu Jinda (牛進達), assisted by Li Hai'an (李海岸) command a navy to attack southern Liaodong Peninsula, and Li Shiji, assisted by Sun Erlang (孫貳朗), command an army to cross the Liao River, both with intent to harass Goguryeo. Both forces consisted of soldiers who were capable of swimming. It was said that both of these forces were successful in inflicting serious losses on Goguryeo forces before withdrawing.
In 648, Emperor Taizong launched another attack over the sea, with Xue Wanche (薛萬徹) in command, assisted by Pei Xingfang (裴行方). A side attack was also launched by Gu Shen'gan (古神感). Believing that Goguryeo had been weakened by these attacks, Emperor Taizong prepared an attack, to be launched in 649, with 300,000 men, to destroy Goguryeo. Some of his officials pointed out that this would require more a year of supply of foods, and that given the massive numbers, land transport would be inadequate and that ships needed to be built. They further pointed out that throughout the disturbances
that caused Sui's destruction and Tang's rise, Jiannan Circuit (劍南道, roughly modern Sichuan
, Yunnan
, and Chongqing
) was undisturbed, and Jiannan was also uninvolved in the 645 campaign, and that Jiannan should therefore be required to build the ships. Emperor Taizong agreed and sent the official Qiang Wei (強偉) to Jiannan to commission the building of the ships, ordering that when the ships are built, they are to be taken down the Yangtze River
and then on East China Sea
, to report to Lai Prefecture. Additional ships were to be built by Yue (越州, roughly modern Shaoxing
, Zhejiang
), Wu (婺州, roughly modern Jinhua
, Zhejiang
), and Hong Prefectures. (Soon, however, it was discovered that the people of Jiannan Circuit were not good at building ships; instead, the people of Jiannan Circuit became only in charge of obtaining the wood for the ships, and the wood was instead shipped to Tan Prefecture (潭州, roughly modern Changsha, Hunan
) to be built into ships.)
Emperor Taizong died in summer 649, and, pursuant to his will, the campaign against Goguryeo was not launched. Li Zhi succeeded him (as Emperor Gaozong), and throughout the early years of Emperor Gaozong's reign, there would be a number of campaigns against Goguryeo and its ally Baekje. Baekje fell to Tang and Silla forces in 660, but the campaigns against Goguryeo would not be successful until 668.
Kim Busik, the author of the Samguk Sagi, who largely agreed with the Chinese accounts of the events, nevertheless commented:
Emperor Taizong of Tang
Emperor Taizong of Tang , personal name Lǐ Shìmín , was the second emperor of the Tang Dynasty of China, ruling from 626 to 649...
(r. 626-649), the second emperor of Chinese
History of China
Chinese civilization originated in various regional centers along both the Yellow River and the Yangtze River valleys in the Neolithic era, but the Yellow River is said to be the Cradle of Chinese Civilization. With thousands of years of continuous history, China is one of the world's oldest...
dynasty Tang Dynasty
Tang Dynasty
The Tang Dynasty was an imperial dynasty of China preceded by the Sui Dynasty and followed by the Five Dynasties and Ten Kingdoms Period. It was founded by the Li family, who seized power during the decline and collapse of the Sui Empire...
, asserting that a campaign against Goguryeo
Goguryeo
Goguryeo or Koguryŏ was an ancient Korean kingdom located in present day northern and central parts of the Korean Peninsula, southern Manchuria, and southern Russian Maritime province....
was necessary to protect Tang's ally Silla
Silla
Silla was one of the Three Kingdoms of Korea, and one of the longest sustained dynasties in...
, as well as to punish Goguryeo's Dae Mangniji (대막리지, 大莫離支, Generalissimo
Generalissimo
Generalissimo and Generalissimus are military ranks of the highest degree, superior to Field Marshal and other five-star ranks.-Usage:...
) Yeon Gaesomun
Yeon Gaesomun
Yeon Gaesomun was a powerful and controversial military dictator and Generalissimo in the waning days of Goguryeo, which was one of the Three Kingdoms of ancient Korea. Yeon is also remembered for a number of successful resistance in military conflicts with Tang Dynasty under Emperor Li Shimin and...
for his killing of Goguryeo's King Yeongnyu
Yeongnyu of Goguryeo
King Yeongnyu of Goguryeo was the 27th king of Goguryeo, the northernmost of the Three Kingdoms of Korea.-Background:He was the younger half-brother of the 26th king Yeong-yang, and son of the 25th king Pyeongwon...
, launched a major campaign against Goguryeo in 644, commanded by himself with the assistance of the generals Li Shiji
Li Shiji
Li Shiji , né Xu Shiji , later known in the reign of Emperor Gaozong of Tang as Li Ji , courtesy name Maogong , formally Duke Zhenwu of Ying , was one of the most celebrated generals early in the Chinese Tang Dynasty...
, Li Daozong
Li Daozong
Li Daozong , courtesy name Chengfan , was an imperial prince of the Chinese dynasty Tang Dynasty. He was a cousin of Emperor Taizong, and in Emperor Taizong's reign commanded forces in campaigns against Eastern Tujue, Tuyuhun, Goguryeo, and Xueyantuo...
, and Zhangsun Wuji
Zhangsun Wuji
Zhangsun Wuji , courtesy name Fuji , formally Duke of Zhao , was a chancellor of the Chinese dynasty Tang Dynasty during the reigns of his brother-in-law Emperor Taizong and nephew Emperor Gaozong...
.
In 645, after defeating the main Goguryeo army, Emperor Taizong appeared poised to march on Goguryeo's capital Pyongyang
Pyongyang
Pyongyang is the capital of the Democratic People's Republic of Korea, commonly known as North Korea, and the largest city in the country. Pyongyang is located on the Taedong River and, according to preliminary results from the 2008 population census, has a population of 3,255,388. The city was...
and conquer Goguryeo, but became bogged down by the strong defenses put up by the defender of Ansi (安市, in modern Anshan, Liaoning
Liaoning
' is a province of the People's Republic of China, located in the northeast of the country. Its one-character abbreviation is "辽" , a name taken from the Liao River that flows through the province. "Níng" means "peace"...
) -- whose name is lost to history but is traditionally believed to be Yang Manchun
Yang Manchun
Yang Manchun is the name given to the Goguryeo commander of Ansi fortress in the 640s.Ansi fortress was located on the Goguryeo-Chinese border, probably present-day Haicheng. Yang is sometimes credited with saving the kingdom by his refusal to surrender the fortress to invading Tang...
-- and was unable to proceed further. Thereafter, for the rest of his reign, Emperor Taizong limited his attack on Goguryeo to harassment raids, and would not again launch a major attack. After Tang and Huige destroyed Xueyantuo
Xueyantuo
The Xueyantuo ' or Syr-Tardush were an ancient Tiele people and khanate in central/northern Asia who were at one point vassals of the Gokturks, later aligning with China's Tang Dynasty against the Eastern Gokturks....
in 646, Emperor Taizong started to built up his army and navy in anticipation for another major campaign in 649, but Emperor Taizong died that same year, stalling the campaign. The Tang Dynasty failed to conquer Goguryeo until 668. In 668, Tang destroyed Goguryeo in alliance with Silla, during the reign of Emperor Taizong's son Emperor Gaozong
Emperor Gaozong of Tang
Emperor Gaozong of Tang , personal name Li Zhi , was the third emperor of the Tang Dynasty in China, ruling from 649 to 683...
.
Background
Failures of three campaignsGoguryeo-Sui Wars
The Goguryeo–Sui Wars were a series of campaigns launched by the Sui Dynasty of China against the Goguryeo of Korea between 598 and 614. It resulted in the defeat of Sui and contributed to the eventual downfall of the dynasty in 618.-Background:...
against Goguryeo
Goguryeo
Goguryeo or Koguryŏ was an ancient Korean kingdom located in present day northern and central parts of the Korean Peninsula, southern Manchuria, and southern Russian Maritime province....
during the reign of Emperor Yang of Sui
Emperor Yang of Sui
Emperor Yang of Sui , personal name Yang Guang , alternative name Ying , nickname Amo , known as Emperor Ming during the brief reign of his grandson Yang Tong), was the second son of Emperor Wen of Sui, and the second emperor of China's Sui Dynasty.Emperor Yang's original name was Yang Ying, but...
had been one of the major reasons for the downfall of Tang Dynasty
Tang Dynasty
The Tang Dynasty was an imperial dynasty of China preceded by the Sui Dynasty and followed by the Five Dynasties and Ten Kingdoms Period. It was founded by the Li family, who seized power during the decline and collapse of the Sui Empire...
's predecessor, Sui Dynasty
Sui Dynasty
The Sui Dynasty was a powerful, but short-lived Imperial Chinese dynasty. Preceded by the Southern and Northern Dynasties, it ended nearly four centuries of division between rival regimes. It was followed by the Tang Dynasty....
. After Tang was founded in 618, Tang's founder Emperor Gaozu
Emperor Gaozu of Tang
Emperor Gāozǔ of Táng , born Lǐ Yuān , courtesy name Shūdé , was the founder of the Tang Dynasty of China, and the first emperor of this dynasty from 618 to 626. Under the Sui dynasty, Li Yuan was the governor in the area of modern-day Shanxi, and was based in Taiyuan.In 615, Li Yuan was assigned...
made peace with Goguryeo's King Yeongnyu
Yeongnyu of Goguryeo
King Yeongnyu of Goguryeo was the 27th king of Goguryeo, the northernmost of the Three Kingdoms of Korea.-Background:He was the younger half-brother of the 26th king Yeong-yang, and son of the 25th king Pyeongwon...
, with the states making an exchange of prisoners of war in 622 and with King Yeongnyu subsequently, in 624, accepting Tang era name and the Tang-created titles of Prince of Liaodong and King of Goguryeo. (At the same time, Emperor Gaozu also created the kings of Goguryeo's two southern neighbors princely titles --Baekje
Baekje
Baekje or Paekche was a kingdom located in southwest Korea. It was one of the Three Kingdoms of Korea, together with Goguryeo and Silla....
's King Mu
Mu of Baekje
King Mu of Baekje was the 30th king of Baekje, one of the Three Kingdoms of Korea. He was the son of King Wideok.- Background :...
as the Prince of Daifang and Silla
Silla
Silla was one of the Three Kingdoms of Korea, and one of the longest sustained dynasties in...
's King Jinpyeong
Jinpyeong of Silla
Jinpyeong of Silla is the 26th king of the Silla Dynasty, one of the Three Kingdoms of Korea. King Jinpyeong followed in the footsteps of King Jinheung by reorganizing the central ruling system, and as many conflicts with Baekje and Goguryeo arose, sent emissaries to improve relations and...
as the Prince of Lelang.)
In 626, Emperor Gaozu's son Li Shimin
Emperor Taizong of Tang
Emperor Taizong of Tang , personal name Lǐ Shìmín , was the second emperor of the Tang Dynasty of China, ruling from 626 to 649...
the Prince of Qin, locked in an intense rivalry with his older brother Li Jiancheng
Li Jiancheng
Li Jiancheng , formally Crown Prince Yin , nickname Pishamen , was a crown prince of the Chinese dynasty Tang Dynasty. He was the oldest son of the founding emperor Emperor Gaozu and therefore was designated crown prince after the founding of the dynasty in 618...
the Crown Prince
Crown Prince
A crown prince or crown princess is the heir or heiress apparent to the throne in a royal or imperial monarchy. The wife of a crown prince is also titled crown princess....
, ambushed and killed Li Jiancheng and another brother who supported Li Jiancheng, Li Yuanji
Li Yuanji
Li Yuanji , formally Prince La of Chao , more commonly known by the title of Prince of Qi , nickname Sanhu , was an imperial prince of the Chinese Tang Dynasty...
the Prince of Qi, at the Incident at Xuanwu Gate
Incident at Xuanwu Gate
The Incident at Xuanwu Gate refers to an incident on July 2, 626, when Li Shimin the Prince of Qin, a son of Emperor Gaozu of Tang , in an intense rivalry with his older brother Li Jiancheng the Crown Prince and fearing that Li Jiancheng was about to kill him, set an ambush at Xuanwu Gate, the...
. He then effectively forced Emperor Gaozu to first create him crown prince and then pass the throne to him (as Emperor Taizong). For most of Emperor Taizong's reign, the relationship between Tang and Goguryeo appeared to be largely friendly, with Emperor Taizong trying to assert more of an overlord role over the dispute between Goguryeo and its rivals Baekje and Silla. For example, soon after Emperor Taizong took the throne in 626, he sent his official Zhu Zishe (朱子奢) to rebuke the three states for attacking each other. In 631, Emperor Taizong sent emissaries to Goguryeo to rebury the Sui war dead, which King Yeongnyu permitted.
In 641, Emperor Taizong sent the official Chen Dade (陳大德) as an emissary to Goguryeo, and on the trip, Chen traveled throughout Goguryeo and met a large number of former Sui soldiers who had settled in Goguryeo, and upon return to the Tang capital Chang'an
Chang'an
Chang'an is an ancient capital of more than ten dynasties in Chinese history, today known as Xi'an. Chang'an literally means "Perpetual Peace" in Classical Chinese. During the short-lived Xin Dynasty, the city was renamed "Constant Peace" ; yet after its fall in AD 23, the old name was restored...
, he reported his findings to Emperor Taizong. Emperor Taizong began contemplating attacking Goguryeo, but then dismissed his own idea, stating that he did not want to trouble the people in the eastern part of his empire.
In 642, however, an event that would trigger Emperor Taizong to rethink his position occurred. King Yeongnyu had been considering to kill his general Yeon Gaesomun
Yeon Gaesomun
Yeon Gaesomun was a powerful and controversial military dictator and Generalissimo in the waning days of Goguryeo, which was one of the Three Kingdoms of ancient Korea. Yeon is also remembered for a number of successful resistance in military conflicts with Tang Dynasty under Emperor Li Shimin and...
, believing Yeon to be violent and criminal. Yeon, after receiving such news, set a trap for the king and a number of officials under guise of a banquet and view of troops, and then killed both the officials and the king. He supported King Yeongnyu's brother Go Jang
Bojang of Goguryeo
Bojang of Goguryeo was the 28th and last king of Goguryeo the northernmost of the Three Kingdoms of Korea. He was placed on the throne by the military leader Yeon Gaesomun...
as king (as King Bojang). Yeon himself took the title of Dae Mangniji (大莫離支, regent) and had the actual control of the government and the military. When the news reached Tang, the official Pei Xingzhuang (裴行莊) suggested attacking Goguryeo, which Emperor Taizong again declined, stating that he mourned King Yeongnyu but that it would be inappropriate to attack Goguryeo in light of King Yeongnyu's death. However, in 643, he again considered military options, but initially considered only ordering the Khitan
Khitan people
thumb|250px|Khitans [[Eagle hunting|using eagles to hunt]], painted during the Chinese [[Song Dynasty]].The Khitan people , or Khitai, Kitan, or Kidan, were a nomadic Mongolic people, originally located at Mongolia and Manchuria from the 4th century...
and the Mohe to harass Goguryeo. Emperor Taizong's brother-in-law, the chancellor Zhangsun Wuji
Zhangsun Wuji
Zhangsun Wuji , courtesy name Fuji , formally Duke of Zhao , was a chancellor of the Chinese dynasty Tang Dynasty during the reigns of his brother-in-law Emperor Taizong and nephew Emperor Gaozong...
opposed this and suggested instead assuring Yeon with offers of peace and then to catch him offguard. Emperor Taizong agreed, and affirmed King Bojang's ascension by creating him the Prince of Liaodong and King of Goguryeo, along with the honorific title of Shang Zhuguo (上柱國).
Later in 643, Silla's Queen Seondeok
Queen Seondeok of Silla
Queen Seondeok of Silla reigned as Queen of Silla, one of the Three Kingdoms of Korea, from 632 to 647. She was Silla's twenty-seventh ruler, and its first reigning queen...
submitted a report claiming that her state was under heavy attack by Baekje, allied with Goguryeo. She requested aid from Tang. Emperor Taizong sent the official Xiangli Xuanjiang (相里玄獎) to Goguryeo to order both it and Baekje to stop attacking Silla. When Xiangli arrived in the Goguryeo capital Pyongyang
Pyongyang
Pyongyang is the capital of the Democratic People's Republic of Korea, commonly known as North Korea, and the largest city in the country. Pyongyang is located on the Taedong River and, according to preliminary results from the 2008 population census, has a population of 3,255,388. The city was...
, Yeon, who was attacking Silla at that time, returned to Pyongyang to meet with Xiangli, but refused to follow Emperor Taizong's order. When Xiangli returned to Chang'an and reported this to Emperor Taizong, Emperor Taizong resolved to attack Goguryeo, stating:
The general Li Shiji
Li Shiji
Li Shiji , né Xu Shiji , later known in the reign of Emperor Gaozong of Tang as Li Ji , courtesy name Maogong , formally Duke Zhenwu of Ying , was one of the most celebrated generals early in the Chinese Tang Dynasty...
was particularly supportive of the plan to attack Goguryeo, and Emperor Taizong decided to prepare for such a campaign, notwithstanding the opposition of Chu Suiliang
Chu Suiliang
Chu Suiliang , courtesy name Dengshan , formally Duke of Henan , was a chancellor of the Chinese dynasty Tang Dynasty, during the reigns of Emperor Taizong and Emperor Taizong's son Emperor Gaozong...
.
Tang advance
In fall 644, in preparation for the attack, Emperor Taizong had his official Yan Lide (閻立德) personally visit the southern Chinese prefectures of Hong (洪州, roughly modern NanchangNanchang
Nanchang is the capital of Jiangxi Province in southeastern China. It is located in the north-central portion of the province. As it is bounded on the west by the Jiuling Mountains, and on the east by Poyang Lake, it is famous for its scenery, rich history and cultural sites...
, Jiangxi
Jiangxi
' is a southern province in the People's Republic of China. Spanning from the banks of the Yangtze River in the north into hillier areas in the south, it shares a border with Anhui to the north, Zhejiang to the northeast, Fujian to the east, Guangdong to the south, Hunan to the west, and Hubei to...
), Rao (饒州, roughly modern Shangrao
Shangrao
Shangrao is a medium-sized prefecture-level city located in the northeast of China's Jiangxi province. According to the 2010 Census, Shangrao has a population of 6,579,714 inhabitants....
, Jiangxi
Jiangxi
' is a southern province in the People's Republic of China. Spanning from the banks of the Yangtze River in the north into hillier areas in the south, it shares a border with Anhui to the north, Zhejiang to the northeast, Fujian to the east, Guangdong to the south, Hunan to the west, and Hubei to...
), and Jiang (江州, roughly modern Jiujiang
Jiujiang
Jiujiang , formerly transliterated Kiukiang, is a prefecture-level city located on the southern shores of the Yangtze River in northwest Jiangxi Province, China. It is the second-largest prefecture-level city in Jiangxi province, the largest one being Nanchang...
, Jiangxi
Jiangxi
' is a southern province in the People's Republic of China. Spanning from the banks of the Yangtze River in the north into hillier areas in the south, it shares a border with Anhui to the north, Zhejiang to the northeast, Fujian to the east, Guangdong to the south, Hunan to the west, and Hubei to...
) to build some 400 supply ships for the campaign. He also had the commandant at Ying Prefecture (營州, roughly modern Zhaoyang, Liaoning
Liaoning
' is a province of the People's Republic of China, located in the northeast of the country. Its one-character abbreviation is "辽" , a name taken from the Liao River that flows through the province. "Níng" means "peace"...
) command the troops from Ying and You (幽州, roughly modern Beijing
Beijing
Beijing , also known as Peking , is the capital of the People's Republic of China and one of the most populous cities in the world, with a population of 19,612,368 as of 2010. The city is the country's political, cultural, and educational center, and home to the headquarters for most of China's...
) prefectures, as well as troops from Khitan
Khitan people
thumb|250px|Khitans [[Eagle hunting|using eagles to hunt]], painted during the Chinese [[Song Dynasty]].The Khitan people , or Khitai, Kitan, or Kidan, were a nomadic Mongolic people, originally located at Mongolia and Manchuria from the 4th century...
, Xi
Kumo Xi
The Kumo Xi ) were a Mongolic steppe people located in current Manchuria from 207 AD to 907 AD. After the death of their ancestor Tadun in 207 they were no longer called Wuhuan but joined the Khitan Xianbei in submitting to the Yuwen Xianbei. Their history is widely linked to the more famous Khitan...
, and Mohe tribes loyal to Tang to make exploratory attacks in the Liaodong region, to test what Goguryeo's responses would be. Apparently to try to ward off the attack, Yeon Gaesomun sent emissaries to offer tributes of platinum. At Chu Suiliang's suggestion, Emperor Taizong rejected the platinum and further accused the emissaries of being loyal not to their king (the deceased King Yeongnyu) but to the regicide (i.e., Yeon); he put them under arrest. In winter 644, he left Chang'an and began his slow advance to the frontier, initially taking most of his officials as well as his crown prince
Crown Prince
A crown prince or crown princess is the heir or heiress apparent to the throne in a royal or imperial monarchy. The wife of a crown prince is also titled crown princess....
Li Zhi
Emperor Gaozong of Tang
Emperor Gaozong of Tang , personal name Li Zhi , was the third emperor of the Tang Dynasty in China, ruling from 649 to 683...
with him, leaving the chancellor Fang Xuanling
Fang Xuanling
Fang Xuanling , formal name Fang Qiao but went by the courtesy name of Xuanling, formally Duke Wenzhao of Liang , was the lead editor of the Book of Jin and one of the most celebrated chancellors of the Chinese dynasty Tang Dynasty, and he and his colleague Du Ruhui, both serving during the reign...
and the general Li Daliang (李大亮) in charge of the capital. He headed first for the eastern capital Luoyang
Luoyang
Luoyang is a prefecture-level city in western Henan province of Central China. It borders the provincial capital of Zhengzhou to the east, Pingdingshan to the southeast, Nanyang to the south, Sanmenxia to the west, Jiyuan to the north, and Jiaozuo to the northeast.Situated on the central plain of...
, where he stayed several months in further preparation.
Around the new year 645, Emperor Taizong issued orders for Zhang Liang
Zhang Liang (Tang Dynasty)
Zhang Liang was a general and official of the Chinese dynasty Tang Dynasty, becoming chancellor late in the reign of Emperor Taizong. He was eventually accused of using witchcraft—a major taboo during China's imperial times—and executed in 646.- Background and service under Li Mi :It is not...
to take some 43,000 soldiers, in 500 ships launching from Lai Prefecture (萊州, roughly modern Laizhou
Laizhou
Laizhou is a county-level city in Yantai Prefecture, Shandong Province, China.As of 2008, Laizhou had a total population of 902,000, out of which 188,000 are urban residents.-External links:* in English...
, Shandong
Shandong
' is a Province located on the eastern coast of the People's Republic of China. Shandong has played a major role in Chinese history from the beginning of Chinese civilization along the lower reaches of the Yellow River and served as a pivotal cultural and religious site for Taoism, Chinese...
), to advance across the Yellow Sea
Yellow Sea
The Yellow Sea is the name given to the northern part of the East China Sea, which is a marginal sea of the Pacific Ocean. It is located between mainland China and the Korean Peninsula. Its name comes from the sand particles from Gobi Desert sand storms that turn the surface of the water golden...
heading toward Pyongyang; and for Li Shiji to command some 60,000 soldiers to head toward Liaodong on land. Emperor Taizong, confident of success, issued an edict that stated, among other things:
In spring 645, Emperor Taizong departed Luoyang, against the advice of the retired general Yuchi Jingde
Yuchi Jingde
Yuchi Jingde , formal name Yuchi Gong but went by the courtesy name of Jingde, formally Duke Zhongwu of E , was a general of the Chinese dynasty Tang Dynasty whose bravery later caused him to be incorporated into Chinese folk religion as a door god, along with Qin Shubao.-During Sui Dynasty:Yuchi...
, who was concerned that a rebellion similar to that Yang Xuangan
Yang Xuangan
Yang Xuangan was an official of the Chinese dynasty Sui Dynasty. He was the son of the powerful official Yang Su, and, as he knew that Emperor Yang was apprehensive of his father, was never quite secure. In 613, when Emperor Yang was attacking Goguryeo, he rebelled near the eastern capital...
started against Emperor Yang in 613 during one of Emperor Yang's Goguryeo campaigns would develop. He left another chancellor, Xiao Yu
Xiao Yu
Xiao Yu , courtesy name Shiwen , formally Duke Zhenbian of Song , was an imperial prince of the Chinese dynasty Liang Dynasty who later became an official for Sui Dynasty and Tang Dynasty, serving as a chancellor at times during the reigns of Emperor Gaozu of Tang and Emperor Taizong of Tang.-...
, in charge of Luoyang. Once he reached Ding Prefecture (定州, roughly modern Baoding
Baoding
-Administrative divisions:Baoding prefecture-level city consists of 3 municipal districts, 4 county-level cities, 18 counties:-Demographics:The Baoding urban area has a population of around 1,006,000 . The population of the Baoding administrative area is 10,890,000. The considerable majority are...
, Hebei
Hebei
' is a province of the People's Republic of China in the North China region. Its one-character abbreviation is "" , named after Ji Province, a Han Dynasty province that included what is now southern Hebei...
), he left Li Zhi there to be in charge of logistics, assisted by Gao Shilian
Gao Shilian
Gao Shilian , formal name Gao Jian but went by the courtesy name of Shilian, formally Duke Wenxian of Shen , was a chancellor of the Chinese dynasty Tang Dynasty...
, Liu Ji
Liu Ji (Tang Dynasty)
Liu Ji , courtesy name Sidao , was a chancellor during the reign of Emperor Taizong of Tang, who was particularly relied on by Emperor Taizong late in his reign...
, Ma Zhou
Ma Zhou
Ma Zhou , courtesy name Binwang , was a chancellor during the reign of Emperor Taizong of Tang. He was initially a commoner and a guest of the general Chang He , and after Chang submitted suggestions that Ma drafted, Emperor Taizong was impressed and retained Ma as an imperial official,...
, Zhang Xingcheng
Zhang Xingcheng
Zhang Xingcheng , courtesy name Deli , formally Duke Ding of Beiping , was a chancellor of the Chinese dynasty Tang Dynasty, during the reigns of Emperor Taizong and Emperor Gaozong.- Background :...
, and Gao Jifu
Gao Jifu
Gao Jifu , formal name Gao Feng but went by the courtesy name of Jifu, formally Duke Xian of Tiao , was a chancellor of the Chinese court in the Tang Dynasty, during the reigns of Emperor Taizong and Emperor Gaozong.- Background :Gao Jifu was born in 596...
. He continued proceeding, with Zhangsun Wuji, Cen Wenben
Cen Wenben
Cen Wenben , courtesy name Jingren , formally Viscount Xian of Jiangling , was a chancellor during the reign of Emperor Taizong of Tang. He was an assistant editor of the Book of Zhou, the official history of Northern Zhou.- Background :Cen Wenben was born in 595, during the reign of Emperor Wen...
, and Yang Shidao
Yang Shidao
Yang Shidao , courtesy name Jingyou , formally Duke Yi of Ande , was a chancellor during the reign of Emperor Taizong of Tang.- Background :It is not known when Yang Shidao was born...
accompanying him. (Cen would die during the campaign.)
Meanwhile, Li Shiji and his deputy, Li Daozong
Li Daozong
Li Daozong , courtesy name Chengfan , was an imperial prince of the Chinese dynasty Tang Dynasty. He was a cousin of Emperor Taizong, and in Emperor Taizong's reign commanded forces in campaigns against Eastern Tujue, Tuyuhun, Goguryeo, and Xueyantuo...
the Prince of Jiangxia (Emperor Taizong's cousin) had, in advance of Emperor Taizong, surprised Goguryeo forces by crossing the Liao River
Liao River
The Liao River is the principal river in northeast China . The province of Liaoning and the Liaodong Peninsula derive their names from the river....
. By summer 645, they had captured Gaemo (蓋牟, in modern Fushun
Fushun
Fushun is a city in Liaoning, China, about 45 km east from Shenyang, with a population about 2,138 090 inhabitants at the 2010 census and an area of 11,271 km2, including 713 km2 of the city proper. Fushun is situated on the Hun He . It was formerly called Fouchouen in French...
, Liaoning
Liaoning
' is a province of the People's Republic of China, located in the northeast of the country. Its one-character abbreviation is "辽" , a name taken from the Liao River that flows through the province. "Níng" means "peace"...
). Meanwhile, Zhang Liang had crossed the Bohai Sea
Bohai Sea
Bohai Sea , also known as Bohai Gulf, Bohai, or Bo Hai, is the innermost gulf of the Yellow Sea on the coast of Northeastern and North China. It is approximately 78,000 km2 Bohai Sea , also known as Bohai Gulf, Bohai, or Bo Hai, is the innermost gulf of the Yellow Sea on the coast of...
and captured Bisa (卑沙, in modern Jinzhou
Jinzhou (Dalian)
Jinzhou District is one of the six districts of Dalian, Liaoning, China. It is located about northeast of the city centre and facing the Bohai Sea to the west and has a longer history than Dalian itself, and used to be a thriving walled city where the officials of this area were dispatched from...
, Dalian
Dalian
Dalian is a major city and seaport in the south of Liaoning province, Northeast China. It faces Shandong to the south, the Yellow Sea to the east and the Bohai Sea to the west and south. Holding sub-provincial administrative status, Dalian is the southernmost city of Northeast China and China's...
, Liaoning
Liaoning
' is a province of the People's Republic of China, located in the northeast of the country. Its one-character abbreviation is "辽" , a name taken from the Liao River that flows through the province. "Níng" means "peace"...
) and sent his forward vessels to the mouth of the Yalu River
Yalu River
The Yalu River or the Amnok River is a river on the border between North Korea and the People's Republic of China....
to try to intimidate Goguryeo forces, but was not heading toward Pyongyang as initially ordered by Emperor Taizong. Soon, Li Shiji and Li Daozong put the Goguryeo city of Yodong/Liaodong (遼東, in modern Liaoyang
Liaoyang
Liaoyang is a city in China, Liaoning province, located in the middle of the Liaodong Peninsula. The city is situated on the T'ai-tzu River and forms with Anshan a built up area of 2,057,200 inhabitants in 2010....
, Liaoning
Liaoning
' is a province of the People's Republic of China, located in the northeast of the country. Its one-character abbreviation is "辽" , a name taken from the Liao River that flows through the province. "Níng" means "peace"...
) -- a city that Emperor Yang had sieged multiple times but was unable to capture—under siege, and after Emperor Taizong arrived himself, Liaodong fell, and another key city, Baegam (白巖, also in modern Liaoyang) surrendered. Emperor Taizong next marched on Ansi.
Battle of Mount Zhubi
Meanwhile, Goguryeo's northern governors Go Yeonsu (高延壽, pinyinPinyin
Pinyin is the official system to transcribe Chinese characters into the Roman alphabet in China, Malaysia, Singapore and Taiwan. It is also often used to teach Mandarin Chinese and spell Chinese names in foreign publications and used as an input method to enter Chinese characters into...
: Gao Yanshou) and Go Hyezin (高惠真, pinyin: Gao Huizhen) put together an army of Goguryeo troops, as well as Mohe tribes allied with Goguryeo, totalling 150,000 men, and headed toward Ansi, intending to relieve it. When Emperor Taizong heard of the impending arrival of the Goguryeo army, he told his officials:
Meanwhile, a senior, experienced Goguryeo officer advised Go Yeonsu:
Go Yeonsu did not accept and continued to proceed to the vicinity of Ansi. Emperor Taizong, in order to further entice him to battle, sent the ethnically Turkic (Ch. Tujue) general Ashina She'er (阿史那社爾) to lead 1,000 Tujue cavalry soldiers forward, and once the Tujue soldiers engaged the Goguryeo forces, they pretended to flee. The Goguryeo forces gave chase and arrived at Ansi.
Emperor Taizong and his generals discussed the strategies, and they ascended the hills to discuss where troops could be hidden and where attacks could be made. Meanwhile, Li Daozong suggested that given that Go Yeonsu and Go Hyezin had this massive of an army, Pyongyang must be poorly defended, and he wanted to personally take 5,000 soldiers to make a surprise attack on Pyongyang, hoping to capture it. Emperor Taizong did not act on Li Daozong's proposal, but instead send a messenger to Go Yeonsu to state:
Go Yeonsu, believing that Emperor Taizong had no further intention to attack, relaxed in his preparations. Meanwhile, Emperor Taizong had Li Shiji take 15,000 soldiers and set up his camp on a hill to the west of the Goguryeo camp, and Zhangsun Wuji take 11,000 soldiers and position himself in a canyon north of the Goguryeo camp. Emperor Taizong himself took 4,000 soldiers and took up position on a hill north of the Goguryeo camp. The next day, July 20, 645, when Go Yeonsu noticed Emperor Taizong's camp to the north, he ordered an attack. As he did, Zhangsun made a surprise attack, and Emperor Taizong also attacked. The Goguryeo forces collapsed, and 20,000 men were killed. Go Yeonsu reorganized his troops and tried to defend his position, but Tang forces had him surrounded, and Zhangsun further destroyed the bridges to prevent a retreat. Two days later, Go Yeonsu and Go Hyezin surrendered with 36,800 men. Emperor Taizong said to them:
Emperor Taizong took 3,500 senior Goguryeo officers, conferred Tang titles on them, and had them sent to Tang proper. He released the other Goguryeo soldiers and sent them back to Pyongyang, but massacred the captured Mohe soldiers—some 3,300. In commemoration of his victory, Emperor Taizong named the location of the battle Mount Zhubi (駐驆山—i.e., "the mount where the imperial horse was").
After the Battle of Mount Zhubi, Yeon Gaesomun sent emissaries to Xueyantuo
Xueyantuo
The Xueyantuo ' or Syr-Tardush were an ancient Tiele people and khanate in central/northern Asia who were at one point vassals of the Gokturks, later aligning with China's Tang Dynasty against the Eastern Gokturks....
's Zhenzhu Khan
Zhenzhu Khan
Zhenzhu Khan , personal name Yi'nan , full regal title Zhenzhupiqie Khan , was a khan of Xueyantuo, under whom Xueyantuo rose from being a vassal of Eastern Tujue to a mighty khanate ruling over northern/central Asia...
Yi'nan, through Mohe intermediaries, to request that he attack Tang, offering to give him great tributes if he would do so. Yi'nan, in awe of Tang power, refused.
Siege of Ansi
Emperor Taizong next prepared to put Ansi under siege, but he had reservations about it. When he discussed the matter with Li Shiji, he stated:(The name of the defending general of Ansi has been lost to history, but is traditionally rendered in Korean popular accounts as Yang Manchun
Yang Manchun
Yang Manchun is the name given to the Goguryeo commander of Ansi fortress in the 640s.Ansi fortress was located on the Goguryeo-Chinese border, probably present-day Haicheng. Yang is sometimes credited with saving the kingdom by his refusal to surrender the fortress to invading Tang...
, even though some Korean historical sources indicated that the name was lost.)
Li Shiji disagreed, however, arguing that as Geonan was to Ansi's south and that the main Tang food supply was coming from Liaodong, that if he attacked Geonan first, the defenders of Ansi would try to cut his supply lines. Emperor Taizong agreed, and Li Shiji began to siege Ansi.
When Emperor Taizong and Li Shiji arrived at Ansi, it was said that the Ansi defenders, upon seeing the banner of the Tang emperor, began to yell insults from the walls. Emperor Taizong was insulted, and Li Shiji received permission to slaughter the city's male inhabitants when it fell—which led to the Ansi defenders fighting even harder. Li Shiji was unable to capture the city for some time. Go Yeonsu and Go Hyezin, who had by now accepted Tang titles, suggested:
Some other officials also suggested:
Emperor Taizong was inclined to accept these proposals, but Zhangsun opposed, stating:
Emperor Taizong agreed with Zhangsun and did not head toward Ogol.
As the siege continued, on an occasion, when Emperor Taizong heard the sounds of chickens and pigs coming out of the city, he opined to Li Shiji that it must be that the Goguryeo defenders were preparing an assault and killing animals beforehand to feast on them. Li Shiji therefore prepared for a night assault, which came that night. Emperor Taizong himself led soldiers to repel the assault, and the Goguryeo forces withdrew within the city again.
Meanwhile, Li Daozong was building a dirt mound to the southeast of the city to use as an attack mechanism, and in response, the Ansi defenders added to the height of the wall to the southeast. This process continued for 60 days, and eventually, the dirt mound got so high that from it, one could easily see inside the city. Li Daozong had his officer Fu Fu'ai (傅伏愛) take position on the dirt mound. Suddenly, the mound had a partial collapse and fell onto the city walls, and the walls collapsed as well. At this moment, Fu, for reasons unexplained in history, left his position, and the Goguryeo forces took the opportunity to attack and capture the dirt mound, and instead used it as part of the defensive bulwarks. Emperor Taizong, in anger, executed Fu in public and ordered a heavy assault on the dirt mound, but could not capture it within three days. Li Daozong bared his feet and begged punishment, but Emperor Taizong pardoned him.
Meanwhile, winter was approaching, and the grass was drying up. Also, the food supplies were running out. On October 13, 645, Emperor Taizong ordered a withdrawal. He gave a demonstration ceremony next to Ansi before withdrawing.
Tang withdrawal
Emperor Taizong suffered an injury during the Goguryeo campaign, which the historical records did not specify the nature or cause of. Later Korean sources speculated that it was an arrow wound suffered during the Siege of Ansi, and the other records speculated that it was an arrow to the Taizong's eye.As the army was crossing the mouth of Liao River, it was trapped by the marshes near the Liao for some time, requiring Zhangsun to command 10,000 men to carry out a project to fill the marshes in to allow the main army to withdraw. As weather was getting increasingly cold at the time, a number of Tang soldiers froze to death.
In all, according to both the medieval Chinese historical source Zizhi Tongjian
Zizhi Tongjian
The Zizhi Tongjian was a pioneering reference work in Chinese historiography, published in 1084, under the form of a chronicles. In 1065 CE, Emperor Yingzong of Song ordered the great historian Sima Guang to lead with other scholars such as his chief assistants Liu Shu, Liu Ban and Fan Zuyu, the...
and the Korean historical source Samguk Sagi
Samguk Sagi
Samguk Sagi is a historical record of the Three Kingdoms of Korea: Goguryeo, Baekje and Silla. The Samguk Sagi is written in Classical Chinese and its compilation was ordered by Goryeo's King Injong Samguk Sagi (History of the Three Kingdoms) is a historical record of the Three Kingdoms of...
, 70,000 Goguryeo people were forcibly moved to Tang territory. Some 40,000 Goguryeo soldiers were killed. According to the Zizhi Tongjian, the Tang forces lost approximately 2,000 men and 70-80% of their horses. However, modern Korean historians doubt the truth of the these records for various reasons. These scholars point to the retreat route of Chinese army, Taizong's acts in withdrawal, and casualties size of Chinese army, which described to Korean damage was a large figure compared with opposing force, and even scaled-down their harmed size.
Emperor Taizong regretted launching the campaign, and sighed, "If Wei Zheng
Wei Zheng
Wei Zheng , courtesy name Xuancheng , formally Duke Wenzhen of Zheng , was a Chinese politician and the lead editor of the Book of Sui, composed in 636...
were still alive, he would not let me launch his campaign." He sent messengers to offer sacrifices to Wei, who had died in 643, and reerected a monument that he had previously built for Wei but which he had destroyed later in 643 after he wrongly believed that the deceased Wei had been in complicity with Hou Junji
Hou Junji
Hou Junji was a major general and chancellor of the Chinese dynasty Tang Dynasty, particularly known for his campaigns against Gaochang and Tuyuhun...
and Du Zhenglun
Du Zhenglun
Du Zhenglun was an official of the Chinese dynasties Sui Dynasty and Tang Dynasty, serving as chancellor during the reign of Emperor Gaozong of Tang.- During Sui Dynasty :...
. He also summoned Wei's wife and children to his presence and awarded them. Due to complications of his injury, he remained in Bing Prefecture (并州, roughly modern Taiyuan
Taiyuan
Taiyuan is the capital and largest city of Shanxi province in North China. At the 2010 census, it had a total population of 4,201,591 inhabitants on 6959 km² whom 3,212,500 are urban on 1,460 km². The name of the city literally means "Great Plains", referring to the location where the Fen River...
, Shanxi
Shanxi
' is a province in Northern China. Its one-character abbreviation is "晋" , after the state of Jin that existed here during the Spring and Autumn Period....
) for several months, before returning to Chang'an, and further transferred a substantial portion of his responsibilities to Li Zhi.
Aftermath
After Emperor Taizong's withdrawal, Yeon Gaesomun became even more defiant toward Tang, and while he sent emissaries to Tang, the letters were not submissive. He was also defiant toward Tang emissaries, and also often sent scouts to venture near Tang borders. Emperor Taizong repeatedly send him edicts ordering him not to attack Silla, but he would not relent. In winter 646, Emperor Taizong issued an edict cutting off relations with Goguryeo and again considering a new campaign against Goguryeo.In 647, Emperor Taizong, after discussions with his officials, who pointed out that the 645 campaign, while unsuccessful, had caused Goguryeo to fall into famine, accepted their proposal of sending relatively small forces to harass Goguryeo's border region to prevent Goguryeo farmers from farming and therefore to create further food supply issues for Goguryeo. He therefore had Niu Jinda (牛進達), assisted by Li Hai'an (李海岸) command a navy to attack southern Liaodong Peninsula, and Li Shiji, assisted by Sun Erlang (孫貳朗), command an army to cross the Liao River, both with intent to harass Goguryeo. Both forces consisted of soldiers who were capable of swimming. It was said that both of these forces were successful in inflicting serious losses on Goguryeo forces before withdrawing.
In 648, Emperor Taizong launched another attack over the sea, with Xue Wanche (薛萬徹) in command, assisted by Pei Xingfang (裴行方). A side attack was also launched by Gu Shen'gan (古神感). Believing that Goguryeo had been weakened by these attacks, Emperor Taizong prepared an attack, to be launched in 649, with 300,000 men, to destroy Goguryeo. Some of his officials pointed out that this would require more a year of supply of foods, and that given the massive numbers, land transport would be inadequate and that ships needed to be built. They further pointed out that throughout the disturbances
Transition from Sui to Tang
The transition from Sui to Tang refers to a period in which the Chinese dynasty Sui Dynasty disintegrated into a number of short-lived states, some ruled by former Sui officials and generals and some by agrarian rebel leaders, and then those states were consolidated into Tang Dynasty, founded by...
that caused Sui's destruction and Tang's rise, Jiannan Circuit (劍南道, roughly modern Sichuan
Sichuan
' , known formerly in the West by its postal map spellings of Szechwan or Szechuan is a province in Southwest China with its capital in Chengdu...
, Yunnan
Yunnan
Yunnan is a province of the People's Republic of China, located in the far southwest of the country spanning approximately and with a population of 45.7 million . The capital of the province is Kunming. The province borders Burma, Laos, and Vietnam.Yunnan is situated in a mountainous area, with...
, and Chongqing
Chongqing
Chongqing is a major city in Southwest China and one of the five national central cities of China. Administratively, it is one of the PRC's four direct-controlled municipalities , and the only such municipality in inland China.The municipality was created on 14 March 1997, succeeding the...
) was undisturbed, and Jiannan was also uninvolved in the 645 campaign, and that Jiannan should therefore be required to build the ships. Emperor Taizong agreed and sent the official Qiang Wei (強偉) to Jiannan to commission the building of the ships, ordering that when the ships are built, they are to be taken down the Yangtze River
Yangtze River
The Yangtze, Yangzi or Cháng Jiāng is the longest river in Asia, and the third-longest in the world. It flows for from the glaciers on the Tibetan Plateau in Qinghai eastward across southwest, central and eastern China before emptying into the East China Sea at Shanghai. It is also one of the...
and then on East China Sea
East China Sea
The East China Sea is a marginal sea east of China. It is a part of the Pacific Ocean and covers an area of 1,249,000 km² or 750,000 square miles.-Geography:...
, to report to Lai Prefecture. Additional ships were to be built by Yue (越州, roughly modern Shaoxing
Shaoxing
Shaoxing is a prefecture-level city in northeastern Zhejiang province, People's Republic of China. Located on the south bank of the Qiantang River estuary, it borders Ningbo to the east, Taizhou to the southeast, Jinhua to the southwest, and Hangzhou to the west. It was once known as "越"...
, Zhejiang
Zhejiang
Zhejiang is an eastern coastal province of the People's Republic of China. The word Zhejiang was the old name of the Qiantang River, which passes through Hangzhou, the provincial capital...
), Wu (婺州, roughly modern Jinhua
Jinhua
Jinhua is a prefecture-level city in central Zhejiang province of Eastern China. It borders the provincial capital of Hangzhou to the northwest, Quzhou to the southwest, Lishui to the south, Taizhou to the east, and Shaoxing to the northeast....
, Zhejiang
Zhejiang
Zhejiang is an eastern coastal province of the People's Republic of China. The word Zhejiang was the old name of the Qiantang River, which passes through Hangzhou, the provincial capital...
), and Hong Prefectures. (Soon, however, it was discovered that the people of Jiannan Circuit were not good at building ships; instead, the people of Jiannan Circuit became only in charge of obtaining the wood for the ships, and the wood was instead shipped to Tan Prefecture (潭州, roughly modern Changsha, Hunan
Hunan
' is a province of South-Central China, located to the south of the middle reaches of the Yangtze River and south of Lake Dongting...
) to be built into ships.)
Emperor Taizong died in summer 649, and, pursuant to his will, the campaign against Goguryeo was not launched. Li Zhi succeeded him (as Emperor Gaozong), and throughout the early years of Emperor Gaozong's reign, there would be a number of campaigns against Goguryeo and its ally Baekje. Baekje fell to Tang and Silla forces in 660, but the campaigns against Goguryeo would not be successful until 668.
Kim Busik, the author of the Samguk Sagi, who largely agreed with the Chinese accounts of the events, nevertheless commented: