 La Grange became a counsellor of Gregory XI (c 1336-78), the French-born pope who ended the period during which the papacy was located in Avignon, France (the so-called Babylonian Captivity) by returning to Rome in 1376.When Gregory died the following year, however, La Grange arrived in Rome too late to take part in the Conclave that elected his successor, Pope Urban VI, an Italian.In protest at the election of a non-French pope, La Grange joined other French Cardinals in re-convening the Conclave in Fondi and elected a rival pope, Clement VII, the first of the so-called Antipopes.