Born in 1301, son of Prince Hisaaki. He became the 9th shogun in 1308 at age seven, succeeding his father, and would be the last shogun of the Kamakura shogunate. His tenure of over 25 years was among the longest in Kamakura history, yet he held no real power whatsoever—the fourteenth regent Hojo Takatoki and the uchikanrei Nagasaki Takasuke and other tokuso retainers monopolized all governance. In 1321, Takatoki retired on grounds of illness but refused to relinquish power, and the era of puppet rule continued in name and in fact. Emperor Go-Daigo's overthrow movement intensified from 1331; the shogunate exiled him to Oki. But in 1333 he escaped, uprisings broke out nationwide, Ashikaga Takauji seized the Rokuhara Tandai in Kyoto, and Nitta Yoshisada's great army advanced on Kamakura. Morikuni resigned and took Buddhist vows. On May 22, 1333, Takatoki and the Hojo clan committed mass suicide at Tosho-ji, ending the shogunate. Morikuni survived briefly, dying later that same year.