Tochigi Prefecture Per Japanese census data,[2] the population of Ichikai has remained relatively steady over the past 30 years.

Ichihane and Kokai villages were created within Haga District on April 1, 1889 with the creation of the modern municipalities system.

Ichikai has a mayor-council form of government with a directly elected mayor and a unicameral town council of 12 members.

Ichikai, together with the other municipalities in Haga District collectively contributes two members to the Tochigi Prefectural Assembly.

In terms of national politics, the town is part of Tochigi 4th district of the lower house of the Diet of Japan.