Year 1509 (MDIX) was a common year starting on Monday (link will display the full calendar) of the Julian calendar.

Events of 1509

January - June

April 21: Henry VIII.

• February 2 - Battle of Diu: The Portuguese defeat a coalition of Indians, Muslims and Italians.
• April 21 - Henry VIII becomes King of England (for 38 years) on the death of his father, Henry VII.
• April 27 - Pope Julius II places Venice under interdict and excommunication for refusing to cede part of Romagna to papal control.
• May 14 - Battle of Agnadello: French forces defeat the Venetians.
• June 11 - Henry VIII of England marries Catherine of Aragon.
• June 19 - Brasenose College, University of Oxford, is founded by a lawyer, Sir Richard Sutton, of Prestbury, Cheshire, and the Bishop of Lincoln, William Smyth.
• June 24 - King Henry VIII of England's and Queen Consort Catherine of Aragon are officially crowned.
• September 10 - 1509 Istanbul earthquake destroys 109 mosques and kills an estimated 10,000 people.

Undated

• Erasmus publishes his most famous work, In Praise of Folly.
• The Royal Dano-Norwegian Navy is founded.
• St Paul's School is founded by John Colet, Dean of St. Paul's Cathedral, London.
• Queen Elizabeth's Grammar School, Blackburn, is founded as a grammar school for boys.
• Afonso de Albuquerque becomes the governor of India.

  Earliest known pocket watch made at Neuremberg, Germany by Peter Henlein

Ongoing

• War of the League of Cambrai (1508-1516)

Births

• January 25 - Giovanni Morone, Italian cardinal (d. 1580)
• July 10 - John Calvin, French religious reformer (d. 1564)
• August 3 - Étienne Dolet, French scholar and printer (d. 1546)
• date unknown
  • Nicholas Bacon, English politician (d. 1579)
  • John Erskine of Dun, Scottish religious reformer (d. 1591)
  • Stanisław Odrowąż, Polish noble (d. 1545)
  • Gonzalo Jiménez de Quesada, lawyer (d. 1579)
  • Bernardino Telesio, Italian philosopher and natural scientist (d. 1588)
  • Kamran Mirza, Mughal prince (d. 1557)
• probable
  • John of Leiden, Dutch Anabaptist leader (d. 1536)

Deaths

• January - Adam Kraft, sculptor and architect
• April 21 - King Henry VII of England (b. 1457)
• May 10 - Caterina Sforza, countess of Forli (b. 1463)
• June 29 - Lady Margaret Beaufort, mother of Henry VII of England (b. 1443)
• July 11 - William II, Landgrave of Hesse (b. 1469)
• July 16 - Mikalojus Radvila the Old, Lithuanian nobleman (b. c. 1450)
• date unknown
  • King João I of Kongo
  • Thomas Long of Draycot, politician (b. c. 1451)
  • João da Nova, Portuguese explorer (b. c. 1460)
  • Giovanni Antonio Sangiorgio, Italian cardinal
  • Hans Seyffer, sculptor and woodcarver (b. c. 1460)
  • İsa Necati, Ottoman poet
  • Shen Zhou, Chinese painter (b. 1427)
  • Viranarasimha Raya, ruler of the Vijayanagar empire