As issues of immigration and integration raise Europe's political temperature, this three-part series examines the history of Muslim immigration to France - a country where debate continues to rage over how to reconcile a long-standing tradition of secularism with religious diversity.

Today, there are an estimated five million Muslims living in France. A century ago, they were referred to as "colonials". During the 1960s, they were known as "immigrants". Today, they are "citizens". But how have the challenges facing each generation of immigrants changed?

The first part of the series tells the story of the 5,000 Muslims who by 1904 were working on the shop floors of Paris, in the soap factories of Marseilles and in the coalfields of the north; of the Muslim soldiers who fought and died for France during the First World War; and the Muslim members of the resistance who helped liberate Paris in 1944. Born as North Africans, many would die for France. But how much did post-war France care about their sacrifices?