When
Minamoto no Yoritomo (head of the Genji clan) raised an army to overthrow the
Taira clan (Heike) in 1180, Yoshikiyo's half-brothers sided with Yoritomo. Shibuya Shigekuni, who was Yoshikiyo's maternal grandfather, sided with the Taira clan, and Oba Kagechika, who was his father-in-law, became the head of the Tairas' army. Shigekuni's longtime kindness made Hideyoshi unable to make up his mind. As a result, although he sided with the Tairas officially, he sided with Yoritomo in fact. His son Yoshikiyo also worried about the same problem, but he decided to side with the Taira clan finally. Yoshikiyo, who was on the Tairas' side, won the
Battle of Ishibashiyama, which turned out to be the first fight of a series of wars. On the other hand, Yoritomo, who was on the Genji side, won the
Battle of Kise-gawa, which broke out next. Yoshikiyo surrendered to Yoritomo, and after that, he sided with the Minamotos and fought in the
Genpei War. In 1185, the Taira were overthrown in the
Battle of Dan-no-ura. After the war ended, his four elder half-brothers were praised for their distinguished military services by Yoritomo, and they got their own feudal estates. But since only Yoshikiyo had been on the enemy side at first, he was not granted any reward. However, he kept on working seriously without resentment. In 1221, the
Jōkyū War broke out. He sided with Bakufu (Kamakura Shoguneto) and won a victory in this war. His distinguished military service and his old achievements were praised by the Bakufu and he became the governor of both
Oki Province and
Izumo Province. == Later life ==