General elections were held in Japan on 31 October 2021, as required by the constitution. Voting took place in all constituencies in order to elect members to the House of Representatives, the lower house of the National Diet. As the constitution requires the cabinet to resign in the first Diet session after a general election, the elections will also lead to a new election for Prime Minister in the Diet, and the appointment of a new cabinet, although ministers may be re-appointed. The election was the first general election of the Reiwa era.
The election followed a tumultuous period in Japanese politics which saw the sudden resignation of Prime Minister Shinzo Abe in 2020 due to health issues and the short premiership of his successor Yoshihide Suga, who stepped down as leader of the ruling Liberal Democratic Party (LDP) after only about a year in office due to poor approval ratings. The period since the previous general election in 2017 also saw the consolidation of much of the country's centre-left into a newly strengthened Constitutional Democratic Party (CDP) and the forming of the left-wing populist party Reiwa Shinsengumi led by former actor Taro Yamamoto.
