Last of the brigade

In a century of horrors which included two world wars, the Holocaust, the Stalin terror and Hiroshima, one event stands out like a blazing beacon. It is the Spanish civil war, whose stark injustice moved tens of thousands of selfless young people from Europe and America to offer their lives in defence of democracy.

They failed, thanks mainly to the craven cowardice of - among others - Britain's Conservative government. Its prime minister, Neville Chamberlain, and his foreign office spokesman, RA Butler, consistently denied the blatant presence of German and Italian troops fighting alongside Franco's fascists. On the basis of Butler's lies, Britain and France enforced a one-sided policy of so-called "non-intervention" which denied the elected government of Spain the weapons it desperately needed.

The cause of the Spanish republic became the great moral crusade for the European and American left in the 1930s. It wasn't an obviously romantic cause, as it had been for Byron in the Greek war for independence. It was a grim battle to halt worldwide fascist aggression and thereby avert a second world war. The volunteers of the International Brigades were, quite simply, fighting to save the world from Nazism.

True, the issues were clouded by sectarianism. Something close to a second civil war broke out between Spanish anarchists and communists behind republican lines. Many of the foreign volunteers were communist party members, and their leaders were often communist. But most were straightforward idealists who had identified a cause worth fighting for. Contrary to legend, they were mostly working class.

Around 2,400 made the journey from Britain to Spain, 526 of them to die there. Today, just 40 remain alive, the last slender link with one of the most extraordinary episodes of European history. To mark Remembrance Day, Guardian writers interviewed all the volunteers who could be traced and were well enough to talk - 23 in all. Their accounts offer a rare insight into the passions and principles that drove thousands of young men and women to risk their lives in a faraway war.

My father, a veteran of the Great War as well as a communist, was among those wonderful volunteers. Later, when Stalin ordered European communist parties to oppose the war against Hitler, he bitterly regretted his loyalty to the USSR. But he remained proud of his part in the International Brigades until his dying day.

On our wall hangs a framed copy of the Orders of the Day for the XVth International Brigade, dated July 5 1937 - the eve of the battle of Brunete. It congratulates the brigade on its successful defence of Madrid, and urges them on to the decisive breakthrough. It declares: "We fight to free Madrid as the first step to freeing Spain. We fight to free Spain as the first step towards freeing the world from fascism." It is signed by the brigade commander, General Copic, and my father.

They failed in the end, at appalling cost. But, in the purest sense of the word, what they did was heroic.