During the Edo period, most of the area was tenryō territory ruled directly by the Tokugawa shogunate through hatamoto administrators.

After the start of the Meiji period, Shinshiro Town in Minamishitara District, Aichi Prefecture was proclaimed on 1 October 1889 with the establishment of the modern municipalities system.

Shinshiro has a mayor-council form of government with a directly elected mayor and a unicameral city legislature of 18 members.

In terms of national politics, the city is part of Aichi District 14 of the lower house of the Diet of Japan.

Shinshiro is a regional commercial center, with the economy concentrated on agriculture, especially chicken farming, and light manufacturing.