• A long time ago - Yamamoto was part of
Toyota District. • April 1, 1955 - Mitoyo District's Tsuji Village, Kouchi Village, Kōda Village, and Saita-Ono Village were merged to create Yamamoto Village. • November 3, 1957 - Renamed Yamamoto Town. • January 1, 2006 - Yamamoto was merged with 6 other towns to create Mitoyo city. ==Administration==