1520

Year 1520 (MDXX) was a leap year starting on Sunday (link will display the full calendar) of the Julian calendar.

Events of 1520

January 18 - King Christian II of Denmark and Norway defeats the Swedes at Lake Asunde.
June - Moctezuma II, Aztec ruler of Tenochtitlan, is declared deposed due to his captivity by conquistador Hernán Cortés. His brother Cuitláhuac rises to the throne.
June 7 - King Henry VIII of England and King Francis I of France meet at the famous Field of Cloth of Gold.
June 15 - Pope Leo X issues the bull Exsurge Domine (Arise O Lord), threatening Martin Luther with excommunication if he does not recant his position on indulgences and other Catholic doctrines.

July 1 - La Noche Triste (Night of Sorrow): The forces of Cuitláhuac, Aztec ruler of Tenochtitlan, gain a major victory against the forces of conquistador Hernán Cortés. This results in the death of about 400 conquistadors and some 2,000 of their Native American allies. However, Cortés and the most skilled of his men manage to escape and later regroup.
July 20 - The Spaniards defeat the Aztecs at Otumba near Lake Texcaco.
September 22 - Suleiman I succeeds his father Selim I as Sultan of the Ottoman Empire.
October - Cuitláhuac, Aztec ruler of Tenochtitlan, dies from smallpox. He is succeeded by his nephew Cuauhtémoc.

November 8 - Stockholm Bloodbath: A successful invasion of Sweden by Danish forces under the command of Christian II of Denmark results in the execution of around 100 persons (mostly nobility and clergy involved in the previous Swedish war effort).
November 28 - After navigating through the South American strait, three ships under the command of Portuguese explorer Ferdinand Magellan reach the Pacific Ocean, becoming the first Europeans to sail from the Atlantic Ocean to the Pacific (the strait was later named the Strait of Magellan).
December 10 - Martin Luther burns a copy of The Book of Canon Law (see Canon Law) and his copy of the Papal bull Exsurge Domine.