[2] Located in the northwestern portion of Gunma Prefecture, almost all of Naganohara has an elevation higher than 500 meters.

Naganohara Town was created within Agatsuma District of Gunma Prefecture on April 1, 1889, with the creation of the modern municipalities system after the Meiji Restoration.

Naganohara has a mayor-council form of government with a directly elected mayor and a unicameral town council of 10 members.

Naganohara collectively with the other municipalities in Agatsuma District, contributes two members to the Gunma Prefectural Assembly.

In terms of national politics, the town is part of Gunma 5th district of the lower house of the Diet of Japan.