The villages of Ōkawa and Koizumi were created within Ōra District, Gunma Prefecture on April 1, 1889 with the creation of the modern municipalities system after the Meiji Restoration. Koizumi was elevated to town status on July 25, 1902.
The creation of Ōkawa and Koizumi as municipalities occurred on April 1, 1889, within the framework of the modern municipality system introduced after the Meiji Restoration. Koizumi's status was upgraded to a town on July 25, 1902.