"The International Brigades (Spanish: Brigadas Internacionales) were military units, made up of volunteers from different countries, who travelled to Spain, in order to fight for the Second Spanish Republic, in the Spanish Civil War, between 1936 and 1939.The number of combatant volunteers has been estimated at between 32,000\u201335,000, though with no more than about 20,000 active at any one time."@en . . .