Gilson taught the history of medieval philosophy at the Sorbonne (1921–32) and then took the chair of medieval philosophy at the Collège de France. In 1929 he helped found the Pontifical Institute of Medieval Studies at Toronto, Canada. Although primarily a historian of philosophy, he was also one of the leaders of the Roman Catholic neo-Thomist movement. He was elected to the French Academy in 1946. His works include The Philosophy of St Thomas Aquinas (1919, trs. 1924); The Christian Philosophy of Saint Augustine (1929, trs. 1960); The Spirit of Mediaeval Philosophy (2 vol., 1932, trs. 1936); God and Philosophy (1941); Being and Some Philosophers (1949); and The Philosopher and Theology (1960, trs. 1962).