At first he worked as gokenin in Kyoto and Kamakura, but when a crisis of Mongol invasion attempts against Japan loomed large, he was appointed to bugyo (magistrate) of Chinzei Toho by the order of the bakufu (Japanese feudal government headed by a shogun) and he was in charge of gunsei (military government) in Kyushu.
はじめは御家人として京都や鎌倉で活動していたが、元寇の危機が強まると幕命により鎮西東方の奉行に任命され、九州の軍政を担当した。