In his native Russia, Paul Leopoldovich Léon was a professor of philosophy and sociology. He left the country after the Russian Revolution of 1917, moving first to London and then to Paris. He and his wife Lucie (who later took the name Lucie Noel) were close friends of James Joyce and the Joyce family. From 1930 to 1940, Paul Léon served as Joyce's agent and business manager, supervising his literary and financial affairs. As a Jew, Paul Léon had to flee the German Occupation of Paris, but he risked his life to return in order to retrieve important papers from the Joyce's home. Much of this material eventually went to the National Library of Ireland, where it remained under seal for 50 years. Paul Léon was arrested by the Nazis in 1941 and sent to a concentration camp, where he died. Lucie later wrote an account of the friendship between the two men. (See "A Critical Companion to James Joyce" by A. Nicholas Fargnoli & Michael Patrick Gillespie.