- May 1 Wars of Scottish Independence end: Treaty of Edinburgh-Northampton - the Kingdom of England recognises the Kingdom of Scotland as an independent state.
- May 12 Holy Roman Emperor Louis IV and assembly of priests select Pietro Rainalducc as anti-Pope Nicolas V; consecrated in Rome by the Bishop of Venice
- May 26 William of Ockham [Occam] forced to flee from Avignon by Pope John XXII
Gregory I
Gregory XIII
Julius II
Julius III
Leo X
Pius V