 On February 1, 1991, the towns of Akita, Kawachi, Tenmei, and Hokubu (all from Hōtaku District) were merged into Kumamoto.On October 6, 2008, the town of Tomiai (from Shimomashiki District) was merged into Kumamoto.On March 23, 2010, the town of Jōnan (also from Shimomashiki District) and the town of Ueki (from Kamoto District) were merged into Kumamoto.