War and Politics

• March 30 - The Sicilian rebellion known as the Sicilian Vespers begins against the rule of Angevin King Charles I of Sicily; over the next 6 weeks, thousands of French are killed. The rebellion forces Charles to abandon the Ninth Crusade while still en route to the target city of Constantinople, and allows King Peter III of Aragon to take over rule of the island from Charles (which in turn leads to Peter's excommunication by Pope Martin IV).
• March - Dafydd ap Gruffydd, brother to Prince of Wales Llywelyn the Last, attacks an English castle; his brother feels compelled to support him despite poor preparation for war, quickly leading to the final English conquest of Wales by King Edward I of England.
• Holy Roman Emperor Rudolph I of Germany invests his sons Albert I of Germany and Rudolph II of Austria as co-rulers of the duchies of Austria and Styria, thus founding the Habsburg dynasty in those territories.
• Battle of Vronen: Floris V, Count of Holland defeats the Frisians and retrieves the body of his father, some 26 years dead.
• King Stefan Dragutin of Serbia breaks his leg while hunting and becomes ill; he gives the throne to his younger brother Stefan Milutin.
• Battle of Forlì between Guelphs and Ghibellines: the French army under Pope Martin IV is defeated by Guido da Montefeltro.

Culture and natural disasters