At the end of World War I ( 1914 - 1918 ), Portugal plunged into a serious economic crisis, with an abrupt rise in prices and unemployment.

The year 1919 was marked by the most significant wave of workers’ struggles, as a result of deteriorating living standards.

Based on the strength of its trade unions, the Portuguese proletariat confronted the increased exploitation with a vast strike movement, aimed at containing the capitalist offensive.

With the support of the União Operária Nacional (the "National Workers’ Union" trade union organisation), the struggles for concrete demands grew. In the heat of this battle, the working class finally won the historic victory of an eight-hour working day.

In September 1919, the trade union organisations took a new step towards stronger unity. They created the CGT (Workers’ General Confederation), which quickly grew to over 100 000 members.

But without a political program, the working class could not define a coherent policy of alliances, and was isolated in its battles against the bosses.

In the meantime, in the wake of the 1917 Russian Revolution’s international repercussions, an enthusiastic movement of solidarity and support for the Bolshevik cause had grown in Portugal.

Different groups had been set up to popularise the experience of the Russian working class. In 1919 the Federação Maximalista Portuguesa ("Portuguese Maximalist Federation") was created. It began publishing the Bandeira Vermelha ("Red Flag") weekly.

From November 1920 onward, several meetings were held at various trade unions’ headquarters with a view to creating a revolutionary vanguard for Portugal’s working class. The following month, an Organising Committee met to create the Portuguese Communist Party, and in January 1921 it began drafting the organisational foundations of this new political organisation.

Unlike what happened in virtually all other European countries, the Portuguese Communist Party was not created as a result of a split in the Socialist Party.

It was essentially set up by militants from the ranks of revolutionary trade-unionism and anarcho-syndicalism, who represented the most active, militant and revolutionary sections of Portugal’s working-class movement.

It is at this embryonic stage in the Communists’ organisational history that the need was felt to create a newspaper of the Portuguese Communist Party.

Seven months after its creation, the first issue of "O Comunista" ("The Communist") was published on 16 October 1921. It was to be followed by "Avante!" ("Forward!") in February 1931.

The PCP set up its first headquarters in the Lisbon street of Rua Arco do Marquês do Alegrete (number 3, 2nd floor). Still in 1921, Communist Centers were opened in the cities of Porto, Evora and Beja.

The creation of the Portuguese Communist Party was not an accident, nor the result of an arbitrary decision. It reflected a historic requirement of Portuguese society and arose out of the Portuguese working-class movement’s development.