Events April 14 — Pope Celestine III succeeds Pope Clement III as the 175th pope. April 17 — Tusculum's destroyed by the Commune of Rome's army. May 12 — Richard I of England marries Berengaria of Navarre. July 12 — Saladin's garrison surrenders, ending the two-year siege of Acre. Conrad of Montferrat, who's negotiated the surrender, raises the banners of the Kingdom of Jerusalem and of the Third Crusade leaders Richard I of England, Philip II of France, and Leopold… (More on 1191)