Taira clan in the context of "Minamoto clan"

The Kamakura period (鎌倉時代, Kamakura jidai; 1185–1333) is a period of Japanese history that marks the governance by the Kamakura shogunate, officially established in 1192 in Kamakura by the first shōgun Minamoto no Yoritomo after the conclusion of the Genpei War, which saw the struggle between the Taira and Minamoto clans. The period is known for the emergence of the samurai, the warrior caste, and for the establishment of feudalism in Japan.

There are various theories as to the year in which the Kamakura period and Kamakura shogunate began. In the past, the most popular theory was that the year was 1192, when Minamoto no Yoritomo was appointed Seii Taishōgun (征夷大将軍). Later, the prevailing theory was that the year was 1185, when Yoritomo established the Shugo (守護), which controlled military and police power in various regions, and the Jitō (地頭), which was in charge of tax collection and land administration. Japanese history textbooks as of 2016 do not specify a specific year for the beginning of the Kamakura period, as there are various theories about the year the Kamakura shogunate was established.

Minamoto (源; Japanese pronunciation: [mʲi.na.mo.to]) was a noble surname bestowed by the Emperors of Japan upon members of the imperial family who were excluded from the line of succession and demoted into the ranks of the nobility since 814. Several noble lines were bestowed the surname, the most notable of which was the Seiwa Genji, whose descendants established the Kamakura and Ashikaga shogunates following the Heian era. The Minamoto was one of the four great clans that dominated Japanese politics during the Heian period in Japanese history—the other three were the Fujiwara, the Taira, and the Tachibana.

In the late Heian period, Minamoto rivalry with the Taira culminated in the Genpei War (1180–1185 AD). The Minamoto emerged victorious and established Japan's first shogunate in Kamakura under Minamoto no Yoritomo, who appointed himself as shōgun in 1192, ushering in the Kamakura period (1192–1333 AD) of Japanese history. The name "Genpei" comes from alternate readings of the kanji "Minamoto" (源 Gen) and "Taira" (平 Hei).

The Genpei War (源平合戦, Genpei Kassen, Genpei-Gassen; 1180–1185) was a national civil war between the Taira and Minamoto clans during the late Heian period of Japan. It resulted in the downfall of the Taira and the establishment of the Kamakura shogunate under Minamoto no Yoritomo, who appointed himself as Shōgun in 1192, governing Japan as a military dictator from the eastern city of Kamakura.

It followed a coup d'état by the Taira in 1179 with the removal of rivals from all government posts, and subsequently banishing them, and a call to arms against the Taira, led by the Minamoto in 1180. The ensuing Battle of Uji took place just outside Kyoto, starting a five-year-long war, concluding with a decisive Minamoto victory in the naval Battle of Dan-no-ura. However, it has been pointed out that the Battle of Ōshū in 1189 was the last battle during this period of civil war, as it completed Yoritomo's nationwide domination through the annexation of Northeast Japan.

Minamoto no Yoritomo (源 頼朝; Japanese pronunciation: [mʲi.na.mo.to no (|) jo.ɾʲi.to.mo], May 9, 1147 – February 9, 1199) was the founder and the first shogun of the Kamakura shogunate, ruling from 1192 until 1199, also the first shogun in the history of Japan to hold de-facto power over Japan. He was married to Hōjō Masako, who acted as regent (shikken) after his death.

Yoritomo was the son of Minamoto no Yoshitomo and belonged to Seiwa Genji's prestigious Kawachi Genji family. After successfully maneuvering himself to the position of rightful heir of the Minamoto clan, he led his clan against the Taira from his capital in Kamakura, beginning the Genpei War in 1180. After five years of civil war, the Minamoto clan finally defeated the Taira in the Battle of Dan-no-ura in 1185. Yoritomo established the supremacy of the samurai caste and the first shogunate (bakufu) which was to be centered around Kamakura, thus beginning the feudal age in Japan, which lasted until the 17th century.

The Tachibana clan (橘氏, Tachibana-uji, Tachibana-shi) was one of the four most powerful court nobility (kizoku or kuge) families in Japan's Nara and early Heian periods—the other three were the Minamoto, the Fujiwara, and the Taira. Members of the Tachibana family often held high court posts within the Daijō-kan (Ministry of State), most frequently Sadaijin (Minister of the Left). Like the other major families at court, they also constantly sought to increase and secure their power by marrying into the imperial family. However, as the Minamoto clan and the Fujiwara clan gained power over the course of the 9th and 10th centuries, the Tachibana were eclipsed and eventually became scattered across the country. Though serving in high government posts outside the capital, they were thus denied the degree of power and influence within the court at Kyoto (Heian-kyō) which they once enjoyed.

The name of Tachibana was bestowed on Agata-no-Inukai no Michiyo by Empress Genmei in 708. She was the wife of Prince Minu, a descendant of Emperor Bidatsu and mothered Princes Katsuragi and Sai. She later married Fujiwara no Fuhito and bore Kōmyōshi (Empress Kōmyō). In 736, Princes Katsuragi and Sai were given the surname Tachibana, renouncing their imperial family membership. They became Tachibana no Moroe and Tachibana no Sai respectively.

Emperor Antoku (安徳天皇, Antoku-tennō; 22 December 1178 – 25 April 1185) was the 81st emperor of Japan, according to the traditional order of succession. His reign spanned the years from 1180 through 1185. His death marked the end of the Heian period and the beginning of the Kamakura period.

During this time, the Imperial House of Japan was involved in a bitter struggle between warring clans. Minamoto no Yoritomo with his cousin Minamoto no Yoshinaka, led a force from the Minamoto clan against the Taira, who controlled the emperor. During the climactic sea Battle of Dan-no-ura in April 1185, Antoku's grandmother Taira no Tokiko took him and plunged with him into the water in the Shimonoseki Straits, drowning the child emperor rather than allowing him to be captured by the opposing forces.

The Battle of Dan-no-ura (壇ノ浦の戦い, Dan-no-ura no tatakai) was a major sea battle of the Genpei War, occurring at Dan-no-ura, in the Shimonoseki Strait off the southern tip of Honshū. On April 25, 1185 (or March 24, 1185 by the official page of Shimonoseki City), the fleet of the Minamoto clan (Genji), led by general Minamoto no Yoshitsune, defeated the fleet of the Taira clan (Heike). The morning rip tide was an advantage for the Taira, but turned to their disadvantage in the afternoon. The young Emperor Antoku was one of those who died among the Taira nobles.

The First Battle of Uji (宇治平等院の戦い, Uji Byōdō-in no Tatakai), alternatively known as "Mochihitos Raising of an Army" in Japan is a battle which took place on June 20, 1180, following Prince Mochihito and Minamoto no Yorimasa's plan to raise an army to overthrow the Taira clan and the issuing of an edict urging the Minamoto clan, major temples, and shrines in the country to revolt.

Due to lack of preparation, the plan was discovered by the Taira, and Prince Mochihito and Yorimasa were defeated, dying at the battle. However, this triggered multiple anti-Taira forces to raise their armies. The battle is famous for having begun the Genpei War.