Taira no Tokuko

Taira no Tokuko (平 徳子^?, 1155–1213), later known as Kenreimon-in (建礼門院^?), was the daughter of the Chancellor Taira no Kiyomori, and empress-consort of Emperor Takakura.

She was also the last Heike Imperial survivor from the great naval battle of Dan-no-ura.

Her life became a compelling narrative which survives as both history and literature.

Tokuko became the adopted daughter of Emperor Go-Shirakawa (後白河天皇,, Go-Shirakawa-tennō^?), the 77th emperor of Japan who reigned from 1155 through 1158. In 1171, when Tokuko was adopted at age 17, the former emperor had abdicated the throne and entered the Buddhist priesthood, taking the Buddhist name of Gyōshin.

In 1172, Tokuko was married to Shirakawa's fourth son, Emperor Takakura. Takakura was also her first cousin as both their mothers were half-sisters. The wedding was an arranged one, as to cement the alliance between the two co-fathers-in-law; Shirakawa sponsored Kiyomori's rise as Chancellor of the Realm, while Kiyomori provided military and financial support to Shirakawa.

Tokuko and Takakura's son, Prince Tokihito, was born in 1178. Just a year later, Kiyomori launched a coup d'état, sacking his political rivals from their posts, banishing them, and replacing them with his allies and clansmen. He even had Shirakawa imprisoned; at this point they fallen out of their political alliance.

...
Wikipedia