Belgian international lawyer and president of the International Peace Bureau. He received the Nobel Prize for Peace in 1913.
La Fontaine took an early interest in the International Peace Bureau, founded in 1882, and was influential in the Bureau’s efforts to bring about The Hague Peace Conferences of 1899 and 1907. He served as president of the Bureau from 1907 until his death in 1943. World War I convinced La Fontaine that the world would establish an international court when peace returned. La Fontaine also promoted the idea of unification of the world’s pacifist organizations.
He was a member of the Belgian delegation to the Paris Peace Conference in 1919 and to the League of Nations Assembly (1920–21). In other efforts to foster world peace, he founded the Centre Intellectuel Mondial (later merged into the League of Nations Institute for Intellectual Co-operation) and proposed such organizations as a world school and university, and a world parliament. In 1907, with Paul Otlet, he founded the Union of International Associations. He also is the co-founder of Institut International de Bibliographie (which later became the International Federation for Information and Documentation, FID) along with Paul Otlet. It was in this role that he and Otlet attended the World Congress of Universal Documentation in 1937.

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