Background
Sadatoki was born in 1271. He was the son of Tokiraune.
Sadatoki was born in 1271. He was the son of Tokiraune.
He became Shikken (Shogunate Prime Minister) in 1284. He was the seventh to assume that post. When Yasumori Adachi, a relative of Sadatoki on his mother's side, became powerful and Yasumori's son, Munekage, was rumored to entertain an ambition to become Shogun, Sadatoki mobilized his forces and killed Yasumori and his son. This was called the Shimotsuki (November) Aftair, having occurred in that month in 1286. In October, 1289, he brought Prince Hisaakira of the Kyoto Imperial Court to Kamakura and made him Shogun. When the Yuan Dynasty of China sent messengers to Japan, he held them in custody and reinforced the defenses of Western Japan against possible invasion from China.
He retired in 1301 and became a Buddhist priest.