Gempei

Gempei War, also known as Genpei War, refers to the conflict in late Heian Japan between the Minamoto (Genji) and Taira (Heike) clans. The war, whose name combines Gen and Hei, lasted roughly from 1180 to 1185 and culminated in a Minamoto victory and the rise of the Kamakura shogunate.

The war grew from political and military rivalry at court, with the Taira clan holding dominant influence over the imperial government while the rising Minamoto faction built strength in the eastern provinces. Disputes over power, succession, and legitimacy intensified centuries of clan factionalism, leading to open conflict after 1180.

Key episodes of the campaign include the early clashes at Uji in 1180, and the later campaigns in western Honshu, which featured major battles such as Ichi-no-Tani and the decisive naval battle of Dan-no-ura in 1185. In the Dan-no-ura encounter, the Taira fleet was defeated, the child-emperor Antoku died, and the Taira line effectively collapsed. Prominent leaders on the Minamoto side included Minamoto no Yoritomo, who would establish the new military government, and his ally Minamoto no Yoshitsune, who played a critical role in the later victories. The Taira patriarch Kiyomori died in 1181, before the war’s final phase.

Aftermath and significance: Minamoto victory shifted political power from the imperial court to warrior authorities, establishing the Kamakura shogunate and inaugurating a feudal, military-centered regime that persisted for centuries. The war is a central subject of the Tale of the Heike, which memorializes its themes of glory, hardship, and the impermanence of power.