Founded by non-Marxist socialists who refused to join the French Section of the Workers' International (SFIO) after its foundation in 1905, and by independent Radicals who refused to join the Radical-Socialist Party when its parliamentary group required formal party membership in 1911, the PRS was a reformist socialist party located between the SFIO and the Radical Socialist Party.
PRS member René Viviani was the first French Minister of Labour (Ministre du Travail et de la Prévoyance sociale) from October 1906 until July 1909).
[1] The PRS was weakened by an ideological contradiction between socialism and reformism in an era where the political divide was very sharp.
In 1945, an attempt failed to recreate it within the Rally of Left Republicans.
Several PRS members headed French cabinets, including Viviani, Aristide Briand, Paul Painlevé, Alexandre Millerand and Joseph Paul-Boncour.