1340

Events 
 Europe has about 74 million inhabitants.
 January 26 – King Edward III of England is declared King of France
 June 24 – The Battle of Sluys is fought between the naval fleets of the Kingdom of England and the Kingdom of France. The former was under the command of Edward III of England and the latter under those of admiral Hue Quiéret and treasurer Nicholas Béhuchet assisted by Genoese mercenary galleys serving under Egidio Bocanegra. The battle ends with the almost complete destruction of the French. Both their commanders were among the casualties. However the mercenaries manage to escape.
 A son of deceased King Christopher II of Denmark is elected to the throne following eight years of Interregnum. He will reign as Valdemar IV of Denmark.