Socialist Party, Japan

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(Japan Socialist Party, JSP)

Creation (1945–51)

Japan's largest socialist party and Japan's main opposition party between 1955 and 1993. As it was formed by an alliance of Christian socialists, millenarian Marxists, trade union members, radicals, and liberals, it is not surprising that the factions of the JSP, like those of the Liberal Democratic Party (LDP), have been a source of conflict throughout the organization's history. In the first years after its formation in 1945, the JSP was propelled into government as the largest partner in two ruling coalitions. However, the experience proved an unhappy one after government policy opened divisions within the party, while the involvement of leading members of the Cabinet in the Shôwa Denkô scandal did much to sully the new party's image.

Contemporary history (1951–1980s)

The JSP divided between left and right socialist parties in 1951 over the issue of Japan's peace settlement with the USA, but reunited in 1955. In the intervening period, the strength of the left-wing faction grew thanks to unprecedented electoral success and it emerged stronger than the JSP's right wing. Despite the merger, factional rivalry continued to such a degree that left-wing activists were able to drive out Nishio Suehiro and 40 of his followers from among groups on the party's right in 1959. This defection had the effect of undermining the JSP's confidence in its own abilities to provide a viable challenge to the LDP for many years afterwards. Indeed, the strength of the party's organization and Diet (the House of Representatives) suffered chronic difficulties from this period. The JSP's lower house strength that had peaked in 1958 at 166, was 118 in 1972.

While the national party has rarely been free from crisis, local party organizations have had some spectacular successes. By the mid-1970s, as many as 137 local chief executives controlled a population of 40 million with the backing of Japan's opposition parties, including the JSP. Many of the JSP's problems have stemmed from its reliance on a combination of the trade union vote and rural constituencies. With a poor organization and few material spoils to compete for, the JSP demonstrated a tendency towards ideological disputes.

Contemporary politics (since 1990s)

The JSP recorded a record low of 69 seats in the 1993 House of Representatives elections. Ironically, this disappointing performance brought the JSP into power at the head of a coalition government for the first time in nearly 50 years. The party continued in government until 1998, but its coalition with its erstwhile foe, the LDP (since 1994), was deeply divisive within its own ranks. In 1996 many members left to form the New Socialist Party. More consequential was the defection in that year of many members to form the Democratic Party of Japan. In 1996 the party changed its name to the Social Democratic Party. As a result of haemorrhaging support in the late 1990s, the socialists became a marginal parliamentary force in the new millennium, when the party's representation declined from nineteen seats (2000) to six seats (2005).


Subjects: Contemporary History (Post 1945).

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