Social Democratic Party of Switzerland

The Social Democratic Party of Switzerland (German: Sozialdemokratische Partei der Schweiz, SP; Romansh: Partida Socialdemocrata da la Svizra), also called the Swiss Socialist Party (French: Parti socialiste suisse; Italian: Partito Socialista Svizzero, PS), is a political party in Switzerland. The SP has had two representatives on the Federal Council since 1960 and received the second-highest number of votes in the 2023 Swiss federal election.

The SP was founded on 21 October 1888 and is currently the second-largest of the four leading coalition political parties in Switzerland. It is positioning itself at the centre-left. Currently, Élisabeth Baume-Schneider and Beat Jans represent the party. As of January 2024, the SP is the second-largest political party in the Federal Assembly.

Amongst all pro-European parties in Switzerland, the SP is the largest, and unlike most other Swiss parties, the SP supports Swiss membership in the European Union. Additionally, it supports labour rights and tax incentives for companies that offer shares to employees. The party is a member of the Progressive Alliance and an associate member of the Party of European Socialists.

Before the establishment of the national SP, there were various 19th-century labour movements in Switzerland such as the Grütli Union, the Swiss Trade Union Federation and several local social democratic parties. Most of these labour parties only lasted a short time, until the foundation of the Social Democratic Party on 21 October 1888 (the Swiss Labour Day). Albert Steck of Bern composed the party's platform which emphasised democracy, rejected revolutionary aspirations, and mandated a democratic solution to the social question. The first party president was Alexander Reichel of Bern.

Two years after the party's foundation, Jakob Vogelsanger was the first Social Democrat to be elected to the National Council. In 1904, the moderate party platform was replaced at a party conference in Aarau with a Marxist program written by Otto Lang. The first-past-the-post voting system for elections to the National Council and the borders of the electorates initially prevented the party from achieving serious political power on the national level, despite growing numbers of supporters. Two popular initiatives for the introduction of a proportional voting system were rejected.

The party's historical archives are hosted today by the Swiss Social Archives, which was founded in 1906 by Paul Pflüger. At a 1912 party conference in Neuchâtel, the question of women's suffrage was debated for the first time. The SP accepted a proposal that committed the party to take any opportunity to "agitate for the introduction of women's suffrage."

Although Switzerland remained neutral in the First World War, it did not avoid the spiralling economic crisis that accompanied it. The resulting social tension was unleashed in 1918 by the labour unions and the SP who organised the 1918 Swiss general strike. The goal of the strike was a fundamental reorganisation of society. The Federal Council issued an ultimatum to the strikers and allowed the military occupation of central points. In this way the strike was ended after four days. Political action was quickly taken to conciliate the strikers with the introduction of a 48-hour working week and a popular initiative on proportional elections to the National Council in the 1918 Swiss referendums which passed on 13 October 1918. In the 1919 Swiss federal election, the SP doubled its mandate from 20 to 41 members.

With the third party platform, adopted in 1920, disagreement within the party grew ever greater. In particular the fact that the platform called for the foundation of a dictatorship of the proletariat during the transitional phase from a capitalist class-based society to a socialist commune sparked violent dispute within the party. In 1921, the party decided not to join the Communist International. The left-wing of the party then split from the SP and founded the Communist Party of Switzerland. In 1926, the SP joined the Labour and Socialist International and continued to be a member of until 1940.