The cities are just north of Nagoya and a part of the Chūkyō Metropolitan Area.

[1] Before the electoral reform of 1994, the area formed part of Aichi 2nd district where four Representatives had been elected by single non-transferable vote.

The by-election to replace Ishida took place on April 24, 2011, the day of the second round of the 2011 unified regional elections when mayors and councils in hundreds of cities, special wards, towns and villages across Japan are elected.

The campaign officially took off on April 12, 2011: The Democratic Party did not nominate a candidate, Nagoya mayor Takashi Kawamura's party Genzei Nippon ("Tax cuts Japan") that won 13 seats in the Aichi assembly election on April 10 nominated journalist Masayo Kawamura; former representative Hideki Niwa ran for the LDP and won the by-election.

In the general House of Representatives election of 2012, Niwa easily defended the seat against former prefectural assemblyman Masaki Amano and former Democrat Tomohiko Mizuno who had represented the Minami-Kantō PR block since 2009.