In 1964 the Youth Council, under the direction of Ramón Piñeiro, expelled the leftist sector, which proceeded to refound the UPG in Santiago de Compostela on July 25, 1964, integrating the Brais Pinto group, former militants of the Federation of the Galicianist Youth[c] (as Celso Emilio Ferreiro) and the Communist Party of Spain (Luís Soto) and independent left nationalists, a total no more than 25 people.

In the first two years the party activities are reduced to sporadic contacts of its members and the publication of the journal Terra e Tempo, in which its first program was published in 1965: U.P.G.

In 1971 the expulsion of Xosé Torres and his followers, who joined the Communist Movement of Spain, left the organization almost without militants in Ferrol and Santiago de Compostela.

It is not until the formation of Galician Revolutionary Students (ERGA) by Manuel Mera in 1972 when the UPG started to increase its social base.

[4] Although the strike failed in its goals, the UPG left this period significantly strengthened, more militants, more prestige among the workers and much more experience.

The document was later also signed by Herriko Alderdi Sozialista, Cymru Goch, PSAN-Provisional, Esquerra Catalana dels Treballadors, Su Populu Sardu and Lucha Occitana.

The UPG also developed contacts after the Carnation Revolution (April 25, 1974) with forces of the Portuguese radical left, specially the Liga de Unidade e Ação Revolucionária (LUAR), the Revolutionary Party of the Proletariat – Revolutionary Brigades (PRP-BR) or the Movement of the Armed Forces (MFA).

[7] Between the months of April and May in 1981 the UPG experienced an internal crisis between the supporters of professionalizing and giving more weight to the BN-PG, that were the minority, and those who opposed them, the majority.

After these dissensions, the UPG turned left and supported campaigns for the ETA prisoners, increased its relations with Herri Batasuna and even made joint events with the Communist Party of Spain (Reconstituted), the political wing of the GRAPO.

In February 1982 the centrist wing of the party left the UPG, led by Pedro Luaces (former secretary general) and strong in Lugo.

After the victory of the PSOE in the elections of 1982, the UPG declared himself opposed to any cooperation, since they saw the socialist government as the kind face of capitalism.

This led to the split in July 1986 of 13 Central Committee members and a few dozen militants who founded the Communist Party of National Liberation.

The party has also focused on social work through the nationalist unionism, unified under the banner Confederación Intersindical Galega (CIG).

On 15 and 16 November the XII Congress was held in Santiago de Compostela with the slogan: O nacionalismo, a alternativa á globalización.