Portal:Catholic Church/Selected anniversaries/May 12
- 1003 - Death of Pope Silvester II
- 1012 - Death of Pope Sergius IV
- 1328 - Antipope Nicholas V, a claimant to the papacy, is consecrated in Rome by the Bishop of Venice.
- 1982 - During a procession outside the shrine of the Virgin Mary in Fátima, Portugal, security guards overpower Juan Fernandez Krohn before he can attack Pope John Paul II with a bayonet. Krohn, an ultraconservative Spanish priest opposed to the Vatican II reforms, decided that the Pope must be killed for being an "agent of Moscow."