As it is known, during the Spanish Civil War, the Republic received relevant state support only from the Soviet Union. The article reviews careers of some Soviet military advisers arrived to the Spanish front.

During Barcelona May Days, clashes broke out between troops of the popular-front government and radical revolutionary forces in May 1937. By analysing the events of the uprising and the following retaliation, the article values the chances of the popular front policy in a special historic constellation – during the revolutionary upheaval.        

The author reviews fractions of the Spanish anarchism in connection to traditional Spanish regionalism – their history and place in the political-ideological map. The study gives weight on anarchist ideas on production, land ownership and industrial governance.

The study reviews the history of popular fronts between the two World Wars, focusing mainly on criteria of interpreting it, and also discusses the reality of ideas and tactics of popular fronts after World War II until recent times. The study aims to rise questions, which induce optimal political answers against present right-extremist and authoritarian global tendencies.