[1] During roughly the first half of that period, the shikken was the de facto military dictator of Japan (not including the independent Northern Fujiwara).
[1] The title of shikken was modified, as second in command to the Tokusō in 1256, but by the Muromachi period (1333–1573) the position, though not abolished, did not even figure in the top ranks.
The word shikken is the on'yomi reading of the combination of the two kanji characters 執 and 権, each meaning "to hold (something in the hand, or a service or ceremony); to administer", "power, authority" respectively.
[1] Tokimasa's son Yoshitoki strengthened the position of shikken by integrating it with the post of Samurai-dokoro[when?
In 1224, Yoshitoki's son Hōjō Yasutoki set up the position of rensho (cosigner), or assistant regent.