The siege of Madrid was the key battle of the war. As General Franco’s nationalist troops closed in on the Spanish capital in the autumn of 1936 Europe watched and waited for city to fall. Instead Madrilenos fought tooth and nail to defend themseleves and helped by volunteers from other countries – the International Brigades – they held out against all the odds until almost the end of the conflict in 1939. Their slogan “No Pasarán” (they will not get past) has become a clarion call for anti-fascists around the world since that time.