When his father died in 1199, Yoriie succeeded him in 1202 to become the second shogun of the Kamakura shogunate. Hojo Tokimasa, the father of Yoriie's mother, Masako, greedy for power, conspired to have Yoriie done away with, enlisting the help of Ano Zensei, but in the fifth month of 1203 Yoriie killed Zensei.
In the seventh month of the same year Yoriie, having fallen gravely ill, turned over the authority of government to his eldest son, Ichiman and his younger brother Scmman, later known as Sanetomo. Hiki Yoshikazu, the grandfather of Ichiman, who shared power in the government with Hojo Tokimasa, concluded that this was a scheme on the part of Tokimasa and consulted with Yoriie on ways to overtlirow Tokimasa, but instead Yoshikazu and his grandson Ichiman were both killed by Tokimasa in the ninth month of 1203. Learning of the murder of his son, Yoriie commanded Wada Yoshimori and his associates to attack Tokimasa, but Yoshi- mori instead went over to Tokimasa’s side. Yoriie was thereupon forced to turn over the position of shogun to his younger brother, Minamoto no Sanetomo, and was confined in the Shuzen-ji temple in the province of Izu, where in the seventh month of 1204 he was put to death by Tokimasa.