POG was founded in October 1977, following a split from the Galician National-Popular Bloc (BN-PG).
The majority of the membership of the Galician People's Assembly also entered the new party.
[1] At its peak POG had around 200 members, mainly based in Vigo and Santiago de Compostela.
In the 1979 general and municipal elections POG formed part of the coalition Galician Unity (Unidade Galega).
In December 1980 the party was reconstructed as Galician Left (Esquerda Galega).