February 7– After a 10-week conclave in Rome to elect a new Pope, Giovanni Maria Ciocchi del Monte, Bishop of Palestrina, is selected on the 61st ballot after Reginald Pole of England falls two votes short of winning. Ciocchi del Monte takes the name Pope Julius III and is crowned the next day, succeeding the late Pope Paul III.[2]
February 25– (10th day of 2nd month of Tenbun 19) In Oita, Ōita Prefecture, an attack within the Ōtomo clan of Japanese samurai takes place after clan leader Ōtomo Yoshikazu seeks to disinherit his oldest son and to make his third son, Ōtomo Shioichimaru, as his designated successor. Supporters of the oldest son, Ōtomo Yoshishige, invade Yoshikazu's home and kill Shioichimaru and four other family members.[3]
March 24– "Rough Wooing": England and France sign the Treaty of Boulogne, by which England withdraws from Boulogne in France and returns territorial gains in Scotland.[5]
April 30–KingTabinshwehti of Burma is assassinated by two of his bodyguards while he is on a hunting trip. The two swordsmen, sent by Smim Sawhtut, Governor of Sittaung, behead the King, and a civil war begins as major governors rebel against the new Burmese King Bayinnaung.[10]
May 6– Italian Protestant Michelangelo Florio, jailed since 1548 before being brought to trial for and sentenced to death for heresy, escapes from prison and is able flee to France.[11]
May 15– The vestments controversy is resolved in the Church of England with a compromise on the style of clothing worn by Anglican priests. John Hopper is allowed ordination as the Bishop of Gloucester without being required to wear Anglican vestments, but must not forbid anyone in his bishoporic from wearing the vestments if they wish.[12]
May 20– The Spanish Catalan city of Cullera is plundered by the Ottoman Empire General Dragut Reis,[13] and most of its inhabitants are sold into slavery in Algeria.
July 25–Capture of Mahdia (1550): Troops commanded by Ottoman General Turgut Reis make a counterattack on the Spanish invaders, led by General Andrea Doria. Both sides sustain heavy losses, and the Spanish succeed in forcing the Ottomans to retreat back inside Mahdia.[15]
September 2 (5th waning of Tawthalin 912 ME) – King Bayinnaung of Burma begins a four-month siege of the former Burmese capital, Toungoo, occupied by the king's rebellious brother Minkhaung.
December 7– Lithuanian noble Barbara Radziwiłł, wife of Sigismund II Augustus, King of Poland and Duke of Lithuania since 1547, has an elaborate coronation in Kraków as Queen consort and Grand Duchess, five months before her death at the age of 30.[52]
Fernández Duro, Cesáreo (1895). Armada Española desde la unión de los reinos de Castilla y Aragón (in Spanish). Vol.I. Madrid, Spain: Sucesores de Rivadeneyra. pp.282–284.
Lipsius, Justus (1978). Iusti Lipsi epistolae (in Dutch). Koninklijke Academie voor Wetenschappen, Letteren en Schone Kunsten van België. p.378. ISBN978-90-6569-655-7. Retrieved 3 October 2023.
Frost, Robert (2015). The Oxford History of Poland-Lithuania. Volume I: The Making of the Polish-Lithuanian Union, 1385-1569. Oxford University Press. ISBN978-0-19-820869-3.
Miscellanea di storia italiana (in Italian). R. Deputazione sovra gli studi di storia patria per le antiche provincie e la Lombardia. 1871. p.170. Retrieved 4 October 2023.