He served the Kamaukura bakufu (Japanese feudal government headed by a shogun) as a gokenin (an immediate vassal of the shogunate in the Kamakura and Muromachi through Edo periods) residing in Kyoto, but he gradually deepened his relationship with the Retired Emperor Gotoba and became a saimen no bushi (group of warriors guarding west side of imperial palace).
在京の御家人として鎌倉幕府に仕えるが、次第に後鳥羽上皇との関係を深め西面の武士となる。