Events of 1340

• 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 is under the command of Edward III of England and the latter under that of admiral Hue Quiéret and treasurer Nicholas Béhuchet assisted by Genoese mercenary galleys under Egidio Bocanegra. The French fleet is virtually destroyed and both commanders are among the casualties.

Undated

• A son of deceased King Christopher II of Denmark is elected to the throne following 8 years of Interregnum. He will reign as Valdemar IV of Denmark.

Births

• March 5 - Cansignorio della Scala, Lord of Verona (d. 1375)
• March 6 - John of Gaunt, 1st Duke of Lancaster (d. 1399)
• October - Geert Groote, Dutch founder of the Brethren of the Common Life (d. 1384)
• November 30 - John, Duke of Berry, son of John II of France (d. 1416)
• date unknown
• Enguerrand VII, Lord of Coucy (d. 1397)
• John of Nepomuk, saint of Bohemia (d. 1393)
• Narayana Pandit, mathematician (d. 1400)
• probable
• Margaret Drummond, queen consort of Scotland (d. 1375)
• Haakon VI of Norway (d. 1380)
• Robert III of Scotland (d. 1406)
• Philip van Artevelde, Flemish patriot (d. 1382)

Also see 1340 births.

Deaths

• March 31 - Ivan I of Moscow (b. 1288)
• April 5 - William Melton, English archbishop
• April 6 - Emperor Basil of Trebizond
• April 7 - Boleslaus George II of Halych (b. 1308), duke of Masovia
• December 2 - Geoffrey le Scrope, Chief Justice of King Edward III of England
• December 4 - Henry Burghersh, English bishop and chancellor (b. 1292)
• December 20 - John I, Duke of Bavaria (b. 1329)
• date unknown
• Simonida, queen consort of Serbia (b. 1294)

Also see 1340 deaths.