|Centuries:||15th century – 16th century – 17th century|
|Decades:||1510s 1520s 1530s – 1540s – 1550s 1560s 1570s|
|Years:||1538 1539 1540 – 1541 – 1542 1543 1544|
- The first official translation of the entire Bible in Swedish
- February 12 – Pedro de Valdivia founds Santiago de Chile.
- May 8 – Hernando de Soto reaches the Mississippi River naming it Rio de Espiritu Santo.
- May 23 – Jacques Cartier departs Saint-Malo France on his third voyage.
- July 9 – Estevão da Gama departs Massawa, leaving behind 400 matchlockmen and 150 slaves under his brother Christovão da Gama, with orders to assist the Emperor of Ethiopia defeat Ahmad ibn Ibrihim al-Ghazi who has invaded his Empire.
- August 29 – The Janissaries of Suleiman the Magnificent take Buda by ruse, hiding themselves as tourists.
- Ottoman Sultan Suleiman the Magnificent seals off The Golden Gate in Jerusalem.
- The Parliament of Ireland declares Henry VIII of England King of Ireland replacing the Lordship of Ireland with the Kingdom of Ireland.
- October – The unsuccessful Algerian campaign of Charles V of Spain Gabsurg