The POSR was founded by a dissidence from the Federation of the Socialist Workers of France (FTSF) led by Jean Allemane.
The party, which along with Allemane was a strong believer of the primacy of syndicalism in politics, became a base of future revolutionary syndicalism and parties of a similar ideology would occasionally be described as Allemaniste.
However, next to the working-class socialism of Allemane, an intellectual socialist movement developed within the POSR, led by Lucien Herr, a librarian.
Overall, the POSR was a moderate reformist party, influenced by possibilism which believed that socialism could be achieved through democratic action, such as decentralization and legislative participation.
In 1905, the PSF was along with the Socialist Party of France a founding member of the French Section of the Workers' International (SFIO).