Strains emerge between Kyoto and Kamakura, with the protector of the emperor a figurehead himself, and in 1221 a war—the Jokyu Incident—breaks out between the cloistered emperor and the Hōjō regent.

The Hōjō forces easily win the war, and the imperial court is brought under direct bakufu control.

The shogun's constables gain greater civil powers, and the court is obliged to seek Kamakura 's approval for all of its actions.

Although deprived of political power, the court is allowed to retain extensive estates with which to sustain the imperial splendor the bakufu needs to help sanction its rule.