Social Democratic Party (Japan)
Japanese political party
The Social Democratic Party (社会民主党, Shakai Minshu-tō; often abbreviated to 社民党, Shamin-tō; SDP) is a political party in Japan that was established in 1996. Since its reformation and name change in 1996, it has advocated pacifism and defined itself as a social-democratic party. It was previously known as the Japan Socialist Party (日本社会党, Nihon Shakaitō; abbreviated to JSP in English).
The party was re-founded in January 1996 by the majority of legislators of the former Japan Socialist Party, which was the largest opposition party in the 1955 System. However, most of those legislators joined the Democratic Party of Japan after that. Five leftist legislators who did not join the SDP formed the New Socialist Party, which lost all its seats in the following election. The SDP enjoyed a short period of government participation from 1993 to 1994 as part of the Hosokawa Cabinet and later formed a coalition government with the Liberal Democratic Party under 81st Prime Minister Tomiichi Murayama of the JSP from 1994 to January 1996. The SDP was part of ruling coalitions between January and November 1996 (First Hashimoto Cabinet) and from 2009 to 2010 (Yukio Hatoyama Cabinet).
In the 2019 Japanese House of Councillors election, the party won four representatives in the National Diet, two in the lower house and two in the upper house. In November 2020, the party entered into a merger agreement with the Constitutional Democratic Party (CDP) with the SDP's members in the Diet caucusing with the CDP. The party president Mizuho Fukushima held her seat and, in the 2022 House of Councillors elections, the party cleared the minimum two percent voter share to maintain its legal political party status.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Aug 12, 2026. The linked authority identifier is Q835109. VIAF identifies the subject as 257560055. The Library of Congress control number is n88061553. 3 of 4 selected statements include explicit references; 1 carry qualifiers and 0 use preferred rank. The first chronological checks are 1996, 1955, 1993 and 1994.
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This entry incorporates text from “Social Democratic Party (Japan)” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.