The Democratic Socialist Party (DSP) was established in 1960 by a breakaway group (led by Suehiro Nishio) of the Japan Socialist Party. It was made up of many members of the former Rightist Socialist Party of Japan, a moderate social-democratic faction that existed between 1948 and 1955. The DSP advocated democratic socialism and was a member of the Socialist International. The party supported construction of a welfare state, opposed totalitarianism, and strongly backed the Japan-US alliance. It derived much of its financial and organizational support from the Domei private-sector labor confederation.
The DSP was dissolved in 1994 to join the New Frontier Party. In 1996, the Japan Socialist Party was transformed into the Social Democratic Party. Two years later, in 1998, the New Frontier Party dissolved and most of its members eventually joined the Democratic Party of Japan. Despite the dissolution of the DSP in 1994, its youth organisation (Minsha Youth) survived until 2003 and was a member of the International Union of Socialist Youth (IUSY). After Minsha Youth was dissolved, some of its former members and independent social democrats formed a new youth organization, the Young Socialists, which retained full membership in IUSY. However, that youth organisation was finally dissolved on 8 March 2008 and abandoned its IUSY membership.
- List of political parties in Japan
- Politics of Japan
- Japan Socialist Party
- Social Democratic Party (Japan)
- Japanese Communist Party
- Clean Government Political Assembly
- Komeito (Former)
- Democratic socialism
- New Frontier Party