Taira clan

The Taira (平; Japanese pronunciation: [taꜜi.ɾa]) was one of the four most important clans that dominated Japanese politics during the Heian period of Japanese history – the others being the Minamoto, the Fujiwara, and the Tachibana. The clan is divided into four major groups, named after the emperors they descended from: Kanmu Heishi, Ninmyō Heishi, Montoku Heishi, and Kōkō Heishi, the most influential of which was the Kanmu Heishi line.

In the twilight of the Heian period, the Taira controlled the boy emperor Antoku (himself the grandson of the powerful Kugyō Taira no Kiyomori) and had effectively dominated the Imperial capital of Heian. However, they were opposed by their rivals the Minamoto clan (the Genji), which culminated in the Genpei War (1180–1185 AD). The five-year-long war concluded with a decisive Taira defeat in the naval Battle of Dan-no-Ura, which resulted in the deaths of Antoku and Taira leaders. Following the war, the victorious Minamoto established Japan's first shogunate in Kamakura. The name "Genpei" comes from alternate readings of the kanji "Minamoto" (源 Gen) and "Taira" (平 Hei).

The clan is commonly referred to as Heishi (平氏; [heꜜi.ɕi, heꜜː-], lit. 'Taira clan') or Heike (平家; [heꜜi.ke, heꜜː-], lit. 'House of Taira'), using the character for Taira (平)'s on'yomi hei, while shi (氏) means "clan", and ke (家) means "house" or "extended family". The clan is the namesake of The Tale of the Heike, an epic account of the Genpei War.

Along with the Minamoto, Taira was one of the honorary surnames given by the emperors of the Heian period (794–1185) to their children and grandchildren who were not considered eligible for the throne.

The clan was founded when the Imperial Court grew too large, and the emperor ordered that the descendants of previous emperors from several generations ago would no longer be princes but would instead be given noble surnames and ranks. The decision became applicable during the reign of Emperor Kanmu (782–805) and thus, together with the Minamoto clan, the Taira clan was born.

Some grandchildren of Emperor Kanmu were the first to bear the name of Taira, after 825. Later, descendants of Emperor Nimmyo, Emperor Montoku and Emperor Koko also received the surname. The specific hereditary lines of these emperors are referred to by the posthumous name of the emperor followed by Heishi, for example Kanmu Heishi.

The Kanmu Heishi line has two major branches. One was founded in 889 by Taira no Takamochi (great-grandson of the 50th Emperor Kanmu, who reigned from 781 to 806) proved to be the strongest and most dominant line during the Heian period. A great-grandson of Takamochi, Taira no Korehira, moved to Ise Province (currently part of Mie Prefecture) and established an important Daimyo dynasty. Masamori, his grandson; and Tadamori, his great-grandson, became loyal supporters of Emperor Shirakawa and Emperor Toba, respectively. Later, Tadamori's son, Taira no Kiyomori, created what was considered the first samurai government in the history of Japan.

Taira no Kiyomori, son and heir of Tadamori, rose to the position of Daijō Daijin (great Minister of State), after his victories in the Hōgen Rebellion (1156) and the Heiji Rebellion (1160). Kiyomori succeeded in enthroning his youngest grandson as Emperor Antoku in 1180, an act that led to the Genpei War (Genpei no Sōran, 1180–1185). The last leader of the Kanmu Heishi bloodline, was eventually destroyed by Minamoto no Yoritomo's armies at the Battle of Dan-no-ura, the last battle of the Genpei War. This story is told in the Heike Monogatari.