Azuma-mura(10309) in Seta-gun, Kasakake-machi(10484) in Nitta-gun and Omama-machi(10501) in Yamada-gun are merged, and Midori-shi(10212) is newly established.
東村(10309)、笠懸町(10484)、大間々町(10501)が合併し、みどり市(10212)を新設