1521

Year 1521 (MDXXI) was a common year starting on Tuesday (link will display the full calendar) of the Julian calendar.

Events of 1521

January - June

* January 3 - Pope Leo X excommunicates Martin Luther in the papal bull "Decet Romanum Pontificem".
* January 22 - Emperor Charles V opens the Diet of Worms.
* January 28 - The Diet of Worms begins, lasting until May 25.
* March 6 - Ferdinand Magellan discovers Guam.
* March 16 - Ferdinand Magellan reaches the Philippines.
* April 7 - Ferdinand Magellan arrives at Cebu.
* April 16 - 18 - Martin Luther is examined before Emperor Charles V and the German Diet of Worms.
* April 24 - Revolt of the Comuneros - Battle of Villalar: Castilian royalists defeat the rebels and execute their three leaders.
* April 26 - Martin Luther leaves Worms and disappears for a year - he is rumored to be murdered, but is actually in hiding at the Wartburg Castle.
* April 27 - Magellan is killed in the Philippines.
* May - War breaks out between Charles V, Holy Roman Emperor and the King of France.
* May 17 - Edward Stafford, 3rd Duke of Buckingham, is executed for treason.
* May 20 - Battle of Pampeluna: The French defeat the Spanish.
* May 25 - The Diet of Worms ends when Charles V, Holy Roman Emperor issues the Edict of Worms, declaring Martin Luther an outlaw.
* June 29 or June 30 - The first document is fully written in Romanian: the letter of Neacşu, a trader from Câmpulung, to Johannes Benkner, the mayor of Braşov, warning that the Ottoman Empire is preparing its troops to cross into Wallachia and Transylvania; the script used is Romanian Cyrillic.
* June 30 - Battle of Esquiroz: French forces under Henri d'Albret, exiled King of Navarre, are defeated by the Spanish and forced to abandon their attempt to recover Henri's kingdom.

July - December

* August 8 - Battle of Tenochtitlan: Hernán Cortés and allied local Indians defeat the Aztec forces of Cuauhtémoc, the last Aztec Emperor.
* August 13 - Emperor Cuauhtémoc surrenders to Hernán Cortés.
* August 23 - Christian II of Denmark is deposed as king of Sweden and Gustav Vasa is elected regent.
* August 29 - Belgrade is captured by the Ottoman army of Suleiman I.
* November 23 - Spanish-German-Papal forces under Prosper Colonna force French Marshal Odet de Lautrec to abandon Milan.

Undated

* Berengairo da Garbi notices the appendix.
* Neacşu's Letter, the oldest surviving Romanian document, is written.
* San Juan Bautista is founded in the Puerto Rican archipelago.
* Rjasan is captured by Moscow.
* The first child is born by Roxelana to Suleyman the Magnificent.

Births

* March 21 - Maurice, Elector of Saxony (d. 1553)
* May 8 - Petrus Canisius, Dutch Jesuit (d. 1597)
* August 4 - Pope Urban VII (d. 1590)
* October 9 - Ottavio Farnese, Duke of Parma (d. 1586)
* December 1 - Takeda Shingen, Japanese warlord (d. 1573)
* December 13 - Pope Sixtus V (d. 1590)
*"date unknown"
**Anne Askew, English Protestant martyr (d. 1546)
**John Aylmer, English divine (d. 1594)
**Thomas Chaloner, English statesman and poet (d. 1565)
**Philippe de Monte, Flemish composer (d. 1603)
**Thomas Wyatt the younger, English rebel (d. 1554)

: "See also ."

Deaths

* April 20 - Zhengde Emperor of China (b. 1491)
* April 25 - Juan López de Padilla, Juan Bravo and Francisco Maldonado, executed Spanish rebels
* April 27 - Ferdinand Magellan, Portuguese explorer (b. c. 1480)
* May 10 - Sebastian Brant, German humanist and satirist (b. 1457)
* May 17 - Edward Stafford, 3rd Duke of Buckingham (executed) (b. 1478)
* June 15 - Tamás Bakócz, Hungarian Catholic cardinal and statesman (b. 1442)
* June 21 - Leonardo Loredan, Doge of Venice (b. 1436)
* July - Juan Ponce de León, Spanish conquistador (b. 1460)
* August 27 - Josquin Des Prez, Flemish composer (b. c. 1450)
* December 1 - Pope Leo X (b. 1475)
* December 13 - King Manuel I of Portugal (b. 1469)
*"date unknown"
**Edward Poyning, Lord Deputy to King Henry VII of England (b. 1459)
**Stephen Hawes, English poet (b. 1502)

: "See also ."