Taking advantage of the boom in municipal mergers, known as the big merger of Heisei, the surrounding municipalities of Miwa-cho, Oe-cho and Yakuno-cho were merged together.
また平成の大合併と呼ばれる市町村合併ブームに乗って、周辺自治体であった三和町･大江町・夜久野町と市町村合併を行った。