Ninety years ago, a Civil War broke out in a then little-known country. For thousands of British, Irish and Commonwealth people, the Spanish Civil War was their main focus for three years. Over 2,500 “British” (including Irish and Commonwealth) men and women fought in the International Brigades or served in the medical services of the Spanish Republic. Over 500 volunteers were to die in Spain. Other “British” volunteers served as mercenary pilots and in the revolutionary militias (including George Orwell); some even served on the side of the rebel forces. At home, thousands participated in ‘Spanish Aid’ activities, raising funds for food ships and medical supplies for Republican Spain. During the Civil War, 4000 Basque refugee children were supported by public donations. Picasso’s Guernica painting toured England to raise funds. This is the story of ordinary men and women, told in their own words and reflecting the whole gamut of emotions from ecstasy to despair. Many volunteers would go on to fight in the Second World War and some became leading figures in post-War Britain. But for many volunteers, the Spanish Civil War was the “Passionate Cause” and the outstanding episode of their lives. This is their story.