Romanian Social Democratic Party (1927–1948)

The majority, which supported affiliation, evolved into the Communist Party of Romania in 1921, while the members who opposed the new orientation formed various political groupings, eventually reorganizing under a central leadership in 1927.

Despite successive declarations in favour of uniting the three parties under a single central leadership, this objective was never completed, as the revolutionary and reformist factions came into open conflict.

[1] Beginning with the late 1920s several groups left the party dissatisfied with what they perceived as the turn of the PSDR leadership to right-wing politics.

Banned in 1938 by the personal dictatorship of King Carol II, the PSD remained active in clandestinity, peacefully resisting to the rise of Fascism, condemning the Iron Guard and the National Legionary State proclaimed in 1940.

[2] In April 1944, the PCR and the PSD formed a United Workers' Front (Frontul Unic Muncitoresc), which was meant to coordinate actions from the left.

Subsequently, PSD entered talks with PCR representative Lucrețiu Pătrășcanu, leading to the creation of the National Democratic Front(Frontul Naţional Democrat, FND) in February 1945 (which grouped the two parties together with Petru Groza's Ploughmen's Front, Mihai Ralea's Socialist Peasants' Party, and Mitiță Constantinescu's Union of Patriots).

Meant as an electoral alliance of the Left, the FND faced accusations from the PSD that it was becoming a tool for the PCR (especially after it had passed resolutions reflecting democratic centralism).

Criticism among socialist groups, as illustrated in a December 1922 caricature by Nicolae Tonitza . The mine owner to the miner: "A socialist, you say? My son is a socialist too, but without going on strike ..., that is why he already has his own capital..."