The CNT which was an anarchist trade union had between 1 and 2 million members which included all sections of the working class in Spanish society. Despite their mistakes the Spanish workers put anarchism into practise as never before. Industry and agriculture were collectivised and ran along anarchist lines throughout most of republican Spain. We are talking here of millions of workers, probably in the order of 5 million as many who were not members of the CNT joined in the constructive activity. One further point about Spain.
Many libertarians claim socialism means forcing people to work for the state at the point of a gun.
In Spain the workers did not work for the state but worked for themselves through the collectives. These delegates elected others to decide on regional and national planning of industry. Not every one was happy with being part of the collective, particularly some small farmers. Rather then being forced to join it was decided they could work their own land and trade with the collectives providing they employed no one and providing they worked all the land. Land that was unused was confiscated by the collective.