Karō
In the Edo period, the policy of "sankin-kōtai" (alternate attendance) required each "daimyō" to place a "karō" in Edo and another in the home "han" (feudal domain). A "karō" who was in charge of a castle was called the "jōdai karō" (城代家老), while the one in Edo was called the "Edo karō" (江戸家老). A general term for a domain-based "karō" is "kunigarō" (国家老). Some domains referred to this position as "bugyō" (奉行) or "toshiyori" (年寄). An example of events involving a "karō" comes from one of the most famous of all samurai tales, "Kanadehon Chūshingura". The final  Asano "daimyō" of the Ako "han" was Asano Naganori. While he was in Edo, he was sentenced to commit seppuku for the offense of drawing a sword against Kira Yoshinaka in Edo Castle. When the shogunate abolished the Ako "han", all the Ako samurai became "rōnin". Ōishi Kuranosuke, the "jōdai karō", led 46 other "rōnin" in a vendetta against Kira. As a result of his leadership in the Forty-seven Ronin affair, Ōishi went down in history as the most famous of all "karō". The shogunate post of "rōjū" (elder) had many similarities to that of "karō". Duty. Basically, he  was allowed to stay away from home because of illness or old age, and remained in the post of a senior until he died once he took office. usually, the person on duty is decided on a monthly basis, and the person on duty makes the decision. the person on duty is called the duty or the moon number by the clan. important matters shall be decided on a regular day by gathering at a Hyōjōsho, etc. and proceeding after a meeting.