Hideyasu participated in Emperor Gotoba's anti shogunate scheme, persuading and inducing Taneyoshi MIURA, the younger brother of the powerful gokenin (an immediate vassal of the shogunate in the Kamakura and Muromachi through Edo periods)Yoshimura MIURA to the Emperor's side.
後鳥羽天皇の討幕計画に参与し、有力御家人の三浦義村の弟・三浦胤義を説得して味方に引き入れた。