The April revolution of 1974 brought a ray of happiness to Portugal and dispelled the melancholia which had been its social hallmark for so long. The mournful fado songs were confined to tourist spots and the liberated generation threw itself into twentieth-century beat music. The Lisbon book fair flooded Avenida da Liberdade with ideas that had previously been available only under the counter, and publishing houses translated instant paperbacks on such forbidden subjects as psychology and social history as well as disseminating Marxism and modern fiction. The communist party organised enormous summer festivals to which the most famous of the world's musical groups were invited and huge crowds spent balmy nights wandering among the hundreds of acres of stalls eating, drinking, listening and fearlessly fraternising. In the euphoria there was little room for recrimination and persecution though a few secret policemen were exposed and incarcerated and some successful members of the business community found it expedient to follow a handful of politicians into temporary exile in Brazil. The soldiers found it as difficult as their predecessors had in 1926 to achieve a stable form of government and a few aspired to replace the monetarist certainties of the old order with new Marxist certainties.

The communists were the first people to claim the revolution as their own. They, almost alone, had survived as a clandestine political force throughout the dictatorship. Unlike the communists of mainland Europe, however, they had not shed their hard-line heritage to court democratic popularity rather than Marxist purity.

Their heroic silver-haired leader, Cunhal, had escaped from prison in 1960 and fled to exile in Moscow. He returned to a tumultuous welcome, but maintained an autocratic control over his party which did not endorse even the mild Soviet reforms of the Khrushchev era let alone the Euro-communism of the west. The hard line did not attract the left-wing intellectuals any more than it attracted the democratic socialists, and it was an anathema to the Catholic provinces of the north. The communist vote fluctuated around one-eighth of the electorate concentrated in two main regions of the country. The first focus of communist mobilisation was the industrial zone facing Lisbon where trade unionism was restored to the workforce with angry urgency.