Sukemori thus rebelled in response to an attempt by Hangaku's older brother Nagamochi (who was also called Sukemochi) to overthrow the Kamakura shogunate, and that Nagamochi was soon felled in Kyoto while Sukemori, based in a fort of Mt.Tossaka (the Tossaka-jo Castle), greatly vexed Moritsuna SASAKI's punitive force.
これは坂額の兄の長茂（資茂とも）の鎌倉幕府打倒計画に呼応したものであり、長茂自身は程なく京において討ち取られるが、資盛は要害の鳥坂城に拠って佐々木盛綱らの討伐軍を散々にてこずらせた。