It was founded in September 1958 in reaction against the SFIO stance on the Algerian War and its acceptance of the Gaullist May 1958 putsch.
Half a dozen SFIO members of the French National Assembly and local elected officials joined the splinter party, as well as members from the (centrist) Radical Party, most notably Pierre Mendès France, former Prime Minister.
None of the PSA deputies were reelected at the November 1958 legislative election.
The PSA merged into the Unified Socialist Party in 1960 as one of its founding organisations.
This article about a political party in France is a stub.