Jōkyū War
With the protector of the Emperor , a figurehead himself, strains emerged between Kyōto and Kamakura, and in 1221 the Jōkyū War broke out between the Cloistered Emperor Go-Toba and the second regent Hōjō Yoshitoki. The Hōjō forces easily won the war, and the imperial court was brought under the direct control of the shogunate. The "shōgun"s constables gained greater civil powers, and the court was obliged to seek Kamakura's approval for all of its actions. Although deprived of political power, the court retained extensive estates.