Viscount was the final daimyō

Daimyo

is a generic term referring to the powerful territorial lords in pre-modern Japan who ruled most of the country from their vast, hereditary land holdings...

 of Yokosuka Domain

Yokosuka Domain

' was a Japanese feudal domain of the Edo period, located in Tōtōmi Province. Yokosuka was a Fudai domain. It was centered at Yokosuka Castle in the Matsuo district of the city of Kakegawa in Shizuoka Prefecture.-History:...

 in Tōtōmi Province

Totomi Province

was a province of Japan in the area of Japan that is today western Shizuoka Prefecture. Tōtōmi bordered on Mikawa, Suruga and Shinano Provinces. Its abbreviated form name was .-History:...

 in late-Edo period

Edo period

The , or , is a division of Japanese history which was ruled by the shoguns of the Tokugawa family, running from 1603 to 1868. The political entity of this period was the Tokugawa shogunate....

 Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

, and the first (and only) daimyō of Hanabusa Domain

Hanabusa Domain

' was a Japanese feudal domain of the early Meiji period, located in Nagasa District, Awa Province. It was centered at what is now the area of the city of Kamogawa in modern Chiba Prefecture.-History:...

 in Awa Province

Awa Province (Chiba)

was a province of Japan in the area of modern Chiba Prefecture. It lies on the tip of the Boso Peninsula , whose name takes its first kanji from the name of Awa Province and its second from Kazusa and Shimōsa Provinces. Its abbreviated form name was or...

 in the early years of the Meiji period

Meiji period

The , also known as the Meiji era, is a Japanese era which extended from September 1868 through July 1912. This period represents the first half of the Empire of Japan.- Meiji Restoration and the emperor :...

.

Tadaatsu was the son of Nishio Tadasaka

Nishio Tadasaka

was a daimyō in late-Edo period Japan, who ruled Yokosuka Domain in Tōtōmi Province.Tadasaka was the second son of Sakai Tadazane, daimyō of Himeji Domain, and was adopted by the heirless 6th daimyō of Yokosuka Domain, Nishio Tadakata, to be his successor...

, the 7th daimyō of Yokosuka Domain. His mother was a daughter of Toki Yorinobu, the daimyō of Numata Domain in Kōzuke Province

Kozuke Province

was an old province located in the Tōsandō of Japan, which today comprises Gunma Prefecture. It is nicknamed as or .The ancient provincial capital was near modern Maebashi. During the Sengoku period, Kōzuke was controlled variously by Takeda Shingen, Uesugi Kenshin, the late Hōjō clan, and...

. He became daimyō of Yokosuka and head of the Nishio clan upon his father's death in 1861.

During the Boshin War

Boshin War

The was a civil war in Japan, fought from 1868 to 1869 between forces of the ruling Tokugawa shogunate and those seeking to return political power to the imperial court....

 of the Meiji Restoration

Meiji Restoration

The , also known as the Meiji Ishin, Revolution, Reform or Renewal, was a chain of events that restored imperial rule to Japan in 1868...

, Tadaatsu's retainers were divided as to whether or not the domain should continue to support the shogunate, or join forces with the Satchō Alliance

Satcho Alliance

The ', or Satchō Alliance was a military alliance between the feudal domains of Satsuma and Chōshū formed in 1866 to combine their efforts to overthrow the Tokugawa shogunate of Japan....

 in support of the new imperial government. Thanks to the persuasion of Yaso Tomiho and Aoyama Zen'ichirō, the pro-shogunate elements in Yokosuka dropped their objections, and the Yokosuka Domain peacefully submitted to the Imperial army. As a gesture of loyalty, Yokosuka Domain contributed forces to assisted the new government in its suppression of remaining pro-Tokugawa partisans in northern Japan. In 1868, due to Tokugawa Iesato

Tokugawa Iesato

Prince was the first head of the Tokugawa clan after the overthrow of the Tokugawa bakufu, and a figure in Japanese politics during the Meiji, Taishō and early Shōwa period Japan.-Early life:...

's entry into the Tōkaidō

Tokaido (region)

The was originally an old Japanese geographical region that made up the gokishichidō system and was situated along the southeastern edge of Honshū, its name literally meaning 'Eastern Sea Way'....

 region as daimyō of the newly created Sunpu Domain

Sunpu Domain

' was a Japanese feudal domain intermittently during the Edo period. It was centered in Suruga Province, in what is now the city of Shizuoka, but at times included Kai and parts of Tōtōmi Provinces. In 1869 the domain was renamed .-History:...

, Tadaatsu was transferred to Hanabusa Domain, in Awa Province

Awa Province (Chiba)

was a province of Japan in the area of modern Chiba Prefecture. It lies on the tip of the Boso Peninsula , whose name takes its first kanji from the name of Awa Province and its second from Kazusa and Shimōsa Provinces. Its abbreviated form name was or...

. Tadaatsu ruled Hanabusa as daimyō until 1869, when he was made han chiji (domainal governor). He finally left Hanabusa after the abolition of the domains

Abolition of the han system

The was an act, in 1871, of the new Meiji government of the Empire of Japan to replace the traditional feudal domain system and to introduce centralized government authority . This process marked the culmination of the Meiji Restoration in that all daimyo were required to return their authority...

 in 1871, and relocated to Tokyo

Tokyo

, ; officially , is one of the 47 prefectures of Japan. Tokyo is the capital of Japan, the center of the Greater Tokyo Area, and the largest metropolitan area of Japan. It is the seat of the Japanese government and the Imperial Palace, and the home of the Japanese Imperial Family...

. He was later created a viscount

Viscount

A viscount or viscountess is a member of the European nobility whose comital title ranks usually, as in the British peerage, above a baron, below an earl or a count .-Etymology:...

 under the kazoku

Kazoku

The was the hereditary peerage of the Empire of Japan that existed between 1869 and 1947.-Origins:Following the Meiji Restoration of 1868, the ancient court nobility of Kyoto regained some of its lost status...

peerage system.

Tadaatsu was married to a daughter of Matsudaira Chikayoshi

Matsudaira Chikayoshi

; was a Japanese samurai of the late Edo period who served as daimyō of the Funai Domain . Served in a variety of positions in the Tokugawa Shogunate, including that of wakadoshiyori. Resigning from the family headship in 1871, he went into retirement.-External links:*...

, daimyō of Kitsuki Domain

Kitsuki Domain

The ' was a Japanese domain of the Edo period, located in modern-day Ōita Prefecture, Kyūshū.-History:At the start of the Edo period, the territory which became Kitsuki was part of the Nakatsu domain , the 399,000 koku territory ruled by Hosokawa Tadaoki...

 in Chikugo Province

Chikugo Province

is the name of a former province of Japan in the area that is today the southern part of Fukuoka Prefecture on Kyūshū. It was sometimes called , with Chikuzen Province...

, and had two daughters, but no male heir.

Tadaatsu died in 1910, at age 61. His grave is at the temple of Myogon-ji at Ageo, Saitama

Ageo, Saitama

is a city located in Saitama, Japan.As of December 1, 2010, the city has an estimated population of 227,127 and the density of 4,986.32 persons per km². The total area is 45.55 km². It is twinned with Ueda, Nagano.- History :...

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