Mergers from April 1, 1999 to Present

• On April 21, 2003 - the cities of Tokuyama
  Tokuyama, Yamaguchi
  was a city located in Yamaguchi Prefecture, Japan.On April 21, 2003 Tokuyama was merged with the city of Shinnan'yō, the town of Kumage, from Kumage District, and the town of Kano, from Tsuno District, to form the new city of Shūnan....
  
   and Shinnan'yō; the town of Kumage
  Kumage, Yamaguchi
  was a town located in Kumage District, Yamaguchi, Japan.On April 21, 2003 Kumage was merged with the town of Kano, from Tsuno District, and the cities of Tokuyama and Shinnan'yō to form the new city of Shūnan....
  
   from Kumage District
  Kumage District, Yamaguchi
  Kumage is a district located in Yamaguchi, Japan.As of 2003, the district has an estimated population of 42,778 and a density of 282.12 persons per km²...
  
  , and the town of Kano
  Kano, Yamaguchi
  was a town located in , Yamaguchi, Japan.On April 21, 2003 Kano merged with the town of Kumage, from Kumage District, and the cities of Tokuyama and Shinnan'yō, to form the new city of Shūnan....
  
   from Tsuno District
  Tsuno District, Yamaguchi
  ' is a former district of Yamaguchi Prefecture. Until April 20, 2003, it consisted of a single town, Kano. On April 21, 2003, Kano was merged with the town of Kumage, from Kumage District, and the cities of Tokuyama, Shinnan'yō, to form the new city of Shūnan and the district was dissolved....
  
   merged to form the city of Shūnan
  Shunan, Yamaguchi
  is a city located in east central Yamaguchi Prefecture, Japan.The city was founded on April 21, 2003, merging two former cities, Tokuyama and Shinnan'yō and two towns, Kano and Kumage....
  
  . Tsuno District
  Tsuno District, Yamaguchi
  ' is a former district of Yamaguchi Prefecture. Until April 20, 2003, it consisted of a single town, Kano. On April 21, 2003, Kano was merged with the town of Kumage, from Kumage District, and the cities of Tokuyama, Shinnan'yō, to form the new city of Shūnan and the district was dissolved....
  
   was dissolved as a result of this merger.

• On October 1, 2004 - the towns of Kuka
  Kuka, Yamaguchi
  was a town located in Ōshima District, Yamaguchi, Japan.On October 1, 2004 Kuka was merged with towns of Ōshima, Tachibana, and Tōwa, all from Ōshima District, to form the new town of Suō-Ōshima....
  
  , Ōshima
  Oshima, Yamaguchi
  was a town located in Ōshima District, Yamaguchi, Japan.On October 1, 2004 Ōshima was merged with towns of Kuka, Tachibana, and Tōwa, all from Ōshima District, to form the new town of Suō-Ōshima....
  
  , Tachibana
  Tachibana, Yamaguchi
  is a town located in Ōshima District, Yamaguchi, Japan.On October 1, 2004 Tachibana was merged with towns of Ōshima, Kuka and Tōwa, all from Ōshima District, to form the new town of Suō-Ōshima....
  
   and Tōwa
  Towa, Yamaguchi
  was a town located in Ōshima District, Yamaguchi, Japan.On October 1, 2004 Tōwa was merged with towns of Ōshima, Kuka and Tachibana, all from Ōshima District, to form the new town of Suō-Ōshima....
  
   (all from Ōshima District
  Oshima District, Yamaguchi
  is a district located in Yamaguchi Prefecture, Japan.-Population:As of 2003, the district has an estimated population of 22,070 and a density of 159.86 persons per km². The total area is 138.06 km².-Geography:...
  
  ) merged to form the town of Suō-Ōshima
  Suo-Oshima, Yamaguchi
  is a town located in Ōshima District, Yamaguchi, Japan.Suō-Ōshima was formed on October 1, 2004 from the merger of the former towns of Ōshima, Kuka, Tachibana and Tōwa, all from towns of Ōshima District....
  
  .

• On October 4, 2004 - the old city of Hikari
  Hikari, Yamaguchi
  is a city located in Yamaguchi Prefecture, Japan.The city was founded three times: April 1, 1943 , July 1, 1955 , and October 4, 2004 ....
  
   and the town of Yamato
  Yamato, Yamaguchi
  was a town located in Kumage District, Yamaguchi, Japan.On October 4, 2004 Yamato was merged with the city of Hikari and no longer exists as an independent municipality....
  
   from Kumage District
  Kumage District, Yamaguchi
  Kumage is a district located in Yamaguchi, Japan.As of 2003, the district has an estimated population of 42,778 and a density of 282.12 persons per km²...
  
   merged to form the new city of Hikari
  Hikari, Yamaguchi
  is a city located in Yamaguchi Prefecture, Japan.The city was founded three times: April 1, 1943 , July 1, 1955 , and October 4, 2004 ....
  
  .

• On November 1, 2004 - the town of Kusunoki
  Kusunoki, Yamaguchi
  was a town located in Asa District, Yamaguchi, Japan.On November 1, 2004 Kusunoki was merged with the city of Ube and no longer exists as an independent entity....
  
   from Asa District
  Asa District, Yamaguchi
  Asa was a district located in Yamaguchi Prefecture. The district had an estimated population of 22,781 within a total area of 89.89 km² ....
  
   merged into the city of Ube
  Ube, Yamaguchi
  is a city located in Yamaguchi Prefecture, Japan on the Seto Inland Sea.As of 2010, the city has an estimated population of 179,000 and the density of 622 persons per km². The total area is 287.69 km².The city was founded on November 1, 1921....
  
  .

• On February 13, 2005 - the old city of Shimonoseki
  Shimonoseki, Yamaguchi
  is a city located in Yamaguchi Prefecture, Japan. It is at the southwestern tip of Honshū, facing the Tsushima Strait and also Kitakyushu across the Kanmon Straits....
  
  ; the towns of Hōhoku
  Hohoku, Yamaguchi
  was a town located in Toyoura District, Yamaguchi, Japan.On February 13, 2005 Hōhoku, along with the towns of Kikugawa, Toyoura and Toyota, all from Toyoura District, was merged into the expanded city of Shimonoseki....
  
  , Kikugawa
  Kikugawa, Yamaguchi
  was a town located in Toyoura District, Yamaguchi, Japan.On February 13, 2005 Kikugawa, along with the towns of Hōhoku, Toyoura and Toyota, all from Toyoura District, was merged into the expanded city of Shimonoseki....
  
  , Toyoura
  Toyoura, Yamaguchi
  was a town located in Toyoura District, Yamaguchi, Japan.On February 13, 2005 Toyoura, along with the towns of Hōhoku, Kikugawa and Toyota, all from Toyoura District, was merged into the expanded city of Shimonoseki....
  
   and Toyota
  Toyota, Yamaguchi
  was a town located in Toyoura District, Yamaguchi, Japan.On February 13, 2005 Toyota, along with the towns of Hōhoku, Kikugawa and Toyoura, all from Toyoura District, was merged into the expanded city of Shimonoseki....
  
   from Toyoura District
  Toyoura District, Yamaguchi
  Toyoura was a district located in Yamaguchi Prefecture. The district area covered the city of Shimonoseki and Toyotamae in the city of Mine.As of 2003, the district had an estimated an area of 491.72 km²...
  
   merged to form the new city of Shimonoseki
  Shimonoseki, Yamaguchi
  is a city located in Yamaguchi Prefecture, Japan. It is at the southwestern tip of Honshū, facing the Tsushima Strait and also Kitakyushu across the Kanmon Straits....
  
  . (Toyoura District
  Toyoura District, Yamaguchi
  Toyoura was a district located in Yamaguchi Prefecture. The district area covered the city of Shimonoseki and Toyotamae in the city of Mine.As of 2003, the district had an estimated an area of 491.72 km²...
  
   was dissolved as a result of this merger.)

• On February 21, 2005 - the old city of Yanai
  Yanai, Yamaguchi
  is a city located in Yamaguchi, Japan.The interchange and the expressway is located in the east.Yanai is bounded by Hikari.-History:The city was founded on March 31, 1954....
  
   and the town of Ōbatake
  Obatake, Yamaguchi
  was a town in Kuga District, Yamaguchi, Japan.On February 21, 2005 Ōbatake was merged into the city of Yanai.As of 2003, the town had an estimated population of 3,583 and a density of 298.33 persons per km². The total area was 12.01 km².-External links:...
  
   from Kuga District
  Kuga District, Yamaguchi
  Kuga is a district located in Yamaguchi, Japan.As of 2005 Census, the district has an estimated population of 6,442. The total area is 10.56 km².The district has one town.*Waki-District Timeline:...
  
   merged to form the new city of Yanai
  Yanai, Yamaguchi
  is a city located in Yamaguchi, Japan.The interchange and the expressway is located in the east.Yanai is bounded by Hikari.-History:The city was founded on March 31, 1954....
  
  .

• On March 6, 2005 - the city of Hagi
  Hagi, Yamaguchi
  is a city located in Yamaguchi, Japan and was incorporated as a city on July 1, 1932. Formerly part of Abu District.On March 6, 2005, the former city of Hagi merged with the towns of Susa and Tamagawa, and the villages of Asahi, Fukue, Kawakami and Mutsumi to form the new city of Hagi.Iwami Airport...
  
  ; the towns of Susa
  Susa, Yamaguchi
  was a town located in Abu District, Yamaguchi, Japan.On March 6, 2005 Susa, along with the town of Tamagawa, and the villages of Asahi, Fukue, Kawakami and Mutsumi, all from Abu District, was merged into the expanded city of Hagi....
  
   and Tamagawa
  Tamagawa, Yamaguchi
  was a town located in Abu District, Yamaguchi, Japan.On March 6, 2005 Tamagawa, along with the town of Susa, and the villages of Asahi, Fukue, Kawakami and Mutsumi, all from Abu District, was merged into the expanded city of Hagi....
  
  , and the villages of Asahi
  Asahi, Yamaguchi
  was a village located in Abu District, Yamaguchi, Japan.On March 6, 2005 Asahi, along with the towns of Susa and Tamagawa, and the villages of Fukue, Kawakami and Mutsumi, all from Abu District, was merged into the expanded city of Hagi....
  
  , Fukue
  Fukue, Yamaguchi
  was a village located in Abu District, Yamaguchi, Japan.On March 6, 2005 Fukue, along with the towns of Susa and Tamagawa, and the villages of Asahi, Kawakami and Mutsumi, all from Abu District, was merged into the expanded city of Hagi....
  
  , Kawakami
  Kawakami, Yamaguchi
  was a village located in Abu District, Yamaguchi, Japan.On March 6, 2005 Kawakami, along with the towns of Susa and Tamagawa, and the villages of Asahi, Fukue and Mutsumi, all from Abu District, was merged into the expanded city of Hagi....
  
   and Mutsumi
  Mutsumi, Yamaguchi
  was a village located in Abu District, Yamaguchi, Japan.On March 6, 2005 Mutsumi, along with the towns of Susa and Tamagawa, and the villages of Asahi, Fukue and Kawakami, all from Abu District, was merged into the expanded city of Hagi....
  
   (all from Abu District
  Abu District, Yamaguchi
  Abu is a district located in Yamaguchi, Japan.As of 2010, the district has an estimated population of 3,731 and a density of 32.1 persons per km²...
  
  ) merged to form the new city of Hagi
  Hagi, Yamaguchi
  is a city located in Yamaguchi, Japan and was incorporated as a city on July 1, 1932. Formerly part of Abu District.On March 6, 2005, the former city of Hagi merged with the towns of Susa and Tamagawa, and the villages of Asahi, Fukue, Kawakami and Mutsumi to form the new city of Hagi.Iwami Airport...
  
  .

• On March 22, 2005 - the city of Nagato
  Nagato, Yamaguchi
  is a city located in Yamaguchi, Japan.The city was founded on March 31, 1954.Nagato consists of five smaller towns that were absorbed over the past several years. The towns are Fukawa, Senzaki, Yuya, Heki and Misumi...
  
  ; and the towns of Heki
  Heki, Yamaguchi
  was a town located in Ōtsu District, Yamaguchi, Japan.On March 22, 2005 Heki, along with the towns of Misumi and Yuya, all from Ōtsu District, was merged into the expanded city of Nagato....
  
  , Misumi
  Misumi, Yamaguchi
  was a town located in Ōtsu District, Yamaguchi, Japan.As of 2003, the town had an estimated population of 6,302 and a density of 93.50 persons per km². The total area was 67.40 km²....
  
   and Yuya
  Yuya, Yamaguchi
  was a town located in Ōtsu District, Yamaguchi, Japan.On March 22, 2005 Yuya, along with the towns of Heki and Misumi, all from Ōtsu District, was merged into the expanded city of Nagato....
  
   from Ōtsu District
  Otsu District, Yamaguchi
  Ōtsu was a district located in Yamaguchi Prefecture, Japan. As of 2003, the district had an estimated population of 18,761...
  
   merged to form the new city of Nagato
  Nagato, Yamaguchi
  is a city located in Yamaguchi, Japan.The city was founded on March 31, 1954.Nagato consists of five smaller towns that were absorbed over the past several years. The towns are Fukawa, Senzaki, Yuya, Heki and Misumi...
  
  . (Ōtsu District
  Otsu District, Yamaguchi
  Ōtsu was a district located in Yamaguchi Prefecture, Japan. As of 2003, the district had an estimated population of 18,761...
  
   was dissolved as a result of this merger.)

• On March 22, 2005 - the city of Onoda
  Onoda, Yamaguchi
  Onoda was a city located in Yamaguchi Prefecture, Japan. The city was founded on November 3, 1940.As of 2003, the city had an estimated population of 44,953 and the density of 1,044.20 persons per km². The total area was 43.05 km²....
  
  ; and the town of San'yō from Asa District
  Asa District, Yamaguchi
  Asa was a district located in Yamaguchi Prefecture. The district had an estimated population of 22,781 within a total area of 89.89 km² ....
  
   merged to form the new city of San'yō-Onoda. (Asa District
  Asa District, Yamaguchi
  Asa was a district located in Yamaguchi Prefecture. The district had an estimated population of 22,781 within a total area of 89.89 km² ....
  
   was dissolved as a result of this merger.)

• On October 1, 2005 - the city of Yamaguchi
  Yamaguchi, Yamaguchi
  is the capital city of Yamaguchi Prefecture, Japan.As of February 1, 2010, the city has an estimated population of 198,971 and a population density of 194.44 persons per km²...
  
   (2nd generation); the town of Tokuji
  Tokuji, Yamaguchi
  was a town located in Saba District, Yamaguchi, Japan.On October 1, 2005 Tokuji, along with the towns of Aio, Ajisu and Ogōri, all from Yoshiki District, was merged into the expanded city of Yamaguchi....
  
   from Saba District
  Saba District, Yamaguchi
  Saba was a district located in Yamaguchi Prefecture, Japan.As of 2003, the district had an estimated population of 7,946 and a density of 27.37 persons per km²...
  
  , and the towns of Aio
  Aio, Yamaguchi
  was a town located in Yoshiki District, Yamaguchi, Japan.On October 1, 2005 Aio, along with the town of Tokuji, from Saba District, and the towns of Ajisu and Ogōri, all from Yoshiki District, was merged into the expanded city of Yamaguchi....
  
  , Ajisu
  Ajisu, Yamaguchi
  was a town located in Yoshiki District, Yamaguchi, Japan.On October 1, 2005 Ajisu, along with the town of Tokuji, from Saba District, and the towns of Aio and Ogōri, all from Yoshiki District, was merged into the expanded city of Yamaguchi....
  
   and Ogōri
  Ogori, Yamaguchi
  was a town located in Yoshiki District, Yamaguchi, Japan.On October 1, 2005 Ogōri, along with the town of Tokuji, from Saba District, and the towns of Aio and Ajisu, all from Yoshiki District, was merged into the expanded city of Yamaguchi....
  
   (all from Yoshiki District
  Yoshiki District, Yamaguchi
  Yoshiki was a district located in Yamaguchi Prefecture. The district had a total estimated population of 39,900 and the total area was 82.98 km²...
  
  ) merged to form the new city of Yamaguchi
  Yamaguchi, Yamaguchi
  is the capital city of Yamaguchi Prefecture, Japan.As of February 1, 2010, the city has an estimated population of 198,971 and a population density of 194.44 persons per km²...
  
  (3rd generation). (Saba District
  Saba District, Yamaguchi
  Saba was a district located in Yamaguchi Prefecture, Japan.As of 2003, the district had an estimated population of 7,946 and a density of 27.37 persons per km²...
  
   and Yoshiki District
  Yoshiki District, Yamaguchi
  Yoshiki was a district located in Yamaguchi Prefecture. The district had a total estimated population of 39,900 and the total area was 82.98 km²...
  
   were both dissolved as a result of this merger.)

• On March 20, 2006 - the city of Iwakuni
  Iwakuni, Yamaguchi
  is a city located in Yamaguchi, Japan.On March 20, 2006, the old city of Iwakuni absorbed the towns of Kuga, Mikawa, Miwa, Nishiki, Shūtō and Yū, and the village of Hongō, all from Kuga District, to form the new, expanded city of Iwakuni.- History :...
  
  ; the towns of Yū
  Yu, Yamaguchi
  was a town in Kuga District, Yamaguchi, Japan.On March 20, 2006 Yū, along with the towns of Kuga, Mikawa, Miwa, Nishiki and Shūtō, and the village of Hongō, all from Kuga District, was merged into the expanded city of Iwakuni....
  
  , Kuga
  Kuga, Yamaguchi
  was a town in Kuga District, Yamaguchi, Japan.On March 20, 2006 Kuga, along with the towns of Mikawa, Miwa, Nishiki, Shūtō and Yū, and the village of Hongō, all from Kuga District, was merged into the expanded city of Iwakuni....
  
  , Shūtō
  Shuto, Yamaguchi
  was a town located in Kuga District, Yamaguchi, Japan.On March 20, 2006 Shūtō, along with the towns of Kuga, Mikawa, Miwa, Nishiki and Yū, and the village of Hongō, all from Kuga District, was merged into the expanded city of Iwakuni....
  
  , Nishiki
  Nishiki, Yamaguchi
  was a town located in Kuga District, Yamaguchi, Japan.On March 20, 2006 Nishiki, along with the towns of Kuga, Mikawa, Miwa, Shūtō and Yū, and the village of Hongō, all from Kuga District, was merged into the expanded city of Iwakuni....
  
  , Mikawa
  Mikawa, Yamaguchi
  was a town located in Kuga District, Yamaguchi, Japan.On March 20, 2006 Mikawa, along with the towns of Kuga, Miwa, Nishiki, Shūtō and Yū, and the village of Hongō, all from Kuga District, was merged into the expanded city of Iwakuni....
  
   and Miwa
  Miwa, Yamaguchi
  was a town located in Kuga District, Yamaguchi, Japan.On March 20, 2006 Miwa, along with the towns of Kuga, Mikawa, Nishiki, Shūtō and Yū, and the village of Hongō, all from Kuga District, was merged into the expanded city of Iwakuni....
  
   and the village of Hongō
  Hongo, Yamaguchi
  was a village located in Kuga District, Yamaguchi, Japan.On March 20, 2006 Hongō, along with the towns of Kuga, Mikawa, Miwa, Nishiki, Shūtō and Yū, all from Kuga District, was merged into the expanded city of Iwakuni....
  
   (all from Kuga District
  Kuga District, Yamaguchi
  Kuga is a district located in Yamaguchi, Japan.As of 2005 Census, the district has an estimated population of 6,442. The total area is 10.56 km².The district has one town.*Waki-District Timeline:...
  
  ) merged to from the new city of Iwakuni
  Iwakuni, Yamaguchi
  is a city located in Yamaguchi, Japan.On March 20, 2006, the old city of Iwakuni absorbed the towns of Kuga, Mikawa, Miwa, Nishiki, Shūtō and Yū, and the village of Hongō, all from Kuga District, to form the new, expanded city of Iwakuni.- History :...
  
  . (There are no longer villages within Yamaguchi Prefecture)

• On March 21, 2008 - the city of Mine
  Mine, Yamaguchi
  is a city located in Yamaguchi, Japan.- History :The city was founded on March 31, 1954 by a merger of municipalities that departed from Mine District ....
  
  absorbed the towns of Mitō
  Mito, Yamaguchi
  was a town located in Mine District, Yamaguchi, Japan.As of 2003, the town has an estimated population of 6,270 and a density of 48.42 persons per km². The total area is 129.49 square kilometers....
  
   and Shūhō
  Shuho, Yamaguchi
  was a town located in Mine District, Yamaguchi, Japan.As of 2003, the town has an estimated population of 6,196 and a density of 53.89 persons per km²...
  
  . Mine District
  Mine District, Yamaguchi
  was a district located in Yamaguchi Prefecture, Japan.On March 20, 2008, the day before its dissolution, the district consisted solely of the towns of Mitō and Shūhō .-History:...
  
  , which comprises solely of those two towns, dissolved upon the merger. http://www.city.mine.lg.jp/mine-gappei/index.html

• On January 16, 2010 - the town of Atō
  Ato, Yamaguchi
  was a town located in Abu District, Yamaguchi, Japan.On January 16, 2010, Atō was merged into the city of Yamaguchi.As of 2003, the town had an estimated population of 8,006 and a density of 27.32 persons per km². The total area was 293.08 km².-External links:...
  
   from Abu District
  Abu District, Yamaguchi
  Abu is a district located in Yamaguchi, Japan.As of 2010, the district has an estimated population of 3,731 and a density of 32.1 persons per km²...
  
   merged into the city of Yamaguchi
  Yamaguchi, Yamaguchi
  is the capital city of Yamaguchi Prefecture, Japan.As of February 1, 2010, the city has an estimated population of 198,971 and a population density of 194.44 persons per km²...
  
  .