After a banking apprenticeship and several years of professional experience in New York, Swiss Guillaume Fatio later became a prominent Swiss banker, historian, and diplomat. He was president of the great European banking institution, the Comptoir d’Escompte, and became a leading authority on the League of Nations. Together with his brother, the architect Edmond Fatio, he campaigned for homeland security, urban planning, health and social care. Due to his excellent knowledge of the Anglo-Saxon World beginning in 1920 he became the official link between Swiss authorities and several International Organizations (International Labour Organisation, League of Nations, Disarmament Conference). He wrote numerous books on local cultural history and became mayor of the municipality Genthod on Lake Genève. He possibly submitted a writing about architecture in the 1912 art competitions, after he had corresponded with Pierre, Baron de Coubertin two years earlier regarding participation.