International Working Union of Socialist Parties

The International Working Union of Socialist Parties (IWUSP; also known as the 2½ International or the Vienna International; German: Internationale Arbeitsgemeinschaft Sozialistischer Parteien, IASP) was a political international for the co-operation of socialist parties. == History == The IWUSP was founded on 27 February 1921 at a conference in Vienna, Austria, by ten parties, including the Independent Social Democratic Party of Germany (USPD), the French Section of the Workers' International (SFIO), the Independent Labour Party (ILP), the Social Democratic Party of Switzerland (SPS), the Social Democratic Party of Austria (SPÖ), and the Federation of Romanian Socialist Parties (FPSR, created by splinter groups of the Socialist Party of Romania).

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