During the Edo period, the area was part of the holdings of Tosa Domain ruled by the Yamauchi clan from their seat at Kōchi Castle.

Following the Meiji Restoration, the town of Goman (後免町) was established within Nagaoka District, Kōchi with the creation of the modern municipalities system on April 1, 1889.

Nankoku has a mayor-council form of government with a directly elected mayor and a unicameral city council of 21 members.

In terms of national politics, the city is part of Kōchi 1st district of the lower house of the Diet of Japan.

Nankoku has good road, rail and air connections and has an economy based on light manufacturing, food processing, agriculture and distribution.

Kochi University's medical school and a branch of the National Institute of Technology and Evaluation are located in Nankoku.