Marc Sangnier (1873-1950) was the instigator of a series of International Democratic Peace Congresses in the 1920s and 1930s. A veteran of the First World War, he ardently wished to 'disarm hatred'. Drawing on his pre-war experience as leader of the Christian Democratic youth movement, the Sillon, he launched a non-governmental movement aimed at youth for the advancement of Franco-German understanding. The Ruhr occupation, undertaken due to war reparations disputes, made the Freiburg Congress of August 1923 particularly audacious as Sangnier and a portion of the French left embraced a non-militarist Germany even if political divisions intruded. Sangnier clashed with Prime Minister Poincare in parliament and withstood the physical violence of the nationalist right on the street for his daring. The advent of Locarno diplomacy and detente from 1925 turned Sangnier's movement from being marginal to an important vehicle for promoting rapprochement, recognized as such by Foreign Minister Aristide Briand, himself the symbol of pacifist hopes.