|Centuries:||15th century – 16th century – 17th century|
|Decades:||1510s 1520s 1530s – 1540s – 1550s 1560s 1570s|
|Years:||1540 1541 1542 – 1543 – 1544 1545 1546|
|1543 by topic|
|Arts and science|
|Lists of leaders|
|Birth and death categories|
|Establishments and disestablishments categories|
|Ab urbe condita||2296|
|English Regnal year||34 Hen. 8 – 35 Hen. 8|
— to —癸卯年十二月初六日
|- Vikram Samvat||1599–1600|
|- Shaka Samvat||1465–1466|
|- Kali Yuga||4644–4645|
|- Ǹrí Ìgbò||543–544|
|Japanese calendar||Tenbun 12
|Juche calendar||N/A (before 1912)|
|Julian calendar||1543 MDXLIII|
|Minguo calendar||369 before ROC
|Thai solar calendar||2086|
|Wikimedia Commons has media related to: 1543|
Year 1543 (MDXLIII) was a common year starting on Monday (link will display the full calendar) of the Julian calendar. It is one of the years sometimes referred to as an "Annus mirabilis" because of its significant publications in science, considered the start of the scientific revolution.
- February 11 – King Henry VIII of England allies with Charles V, Holy Roman Emperor, against France.
- February 21 – Battle of Wayna Daga: A joint Ethiopian-Portuguese force of 8,500 under Emperor Gelawdewos of Ethiopia defeats Imam Ahmad ibn Ibrihim al-Ghazi's army of over 14,000, ending the Ethiopian–Adal war.
- King Gustav Vasa's troops crush the forces of Swedish peasant rebel Nils Dacke in battle, ending the uprising. Dacke escapes but is captured and killed in the summer.
- Consolidating Act of Welsh Union: The Parliament of England establishes counties and regularises parliamentary representation in Wales.
- April – Campaign of Suleiman: Suleiman the Magnificent, Ottoman Emperor, revives the Little War in Hungary.
- May – Nicolaus Copernicus publishes De revolutionibus orbium coelestium (On the Revolutions of the Heavenly Spheres) in Nuremberg, offering mathematical arguments for the existence of the heliocentric universe, denying the geocentric model. Copernicus dies on May 24 in Frombork at the age of 70.
- July 1 – Treaty of Greenwich between England and Scotland (repudiated by Scotland December 11).
- July 12 – King Henry VIII of England marries Catherine Parr. It is the sixth and last of Henry's marriages and the third of Catherine's. Princess Elizabeth attends the wedding. This month, the Parliament of England passes the Third Succession Act restoring the Princesses Mary and Elizabeth, Henry's daughters, to the line of succession to the English throne.
- July 25–August 10 – Siege of Esztergom: Suleiman the Magnificent, Ottoman Emperor, besieges and takes Esztergom in Hungary from the Holy Roman Empire.
- August 6–22 – Siege of Nice: Ottoman Empire and French forces (under the Franco-Ottoman alliance) led by Admiral Hayreddin Barbarossa besiege and take Nice.
- September–October – Landrecies in Picardy is besieged by forces under Charles V, Holy Roman Emperor, but the siege is withdrawn on the approach of the French army.
- September – Campaign of Suleiman: Suleiman the Magnificent captures the Hungarian coronation city of Székesfehérvár. The city will be occupied by the Ottoman Empire for 145 years.
Date unknown 
- Andreas Vesalius publishes De humani corporis fabrica (On the Fabric of the Human Body), revolutionising the science of human anatomy.
- Martin Luther publishes On the Jews and Their Lies.
- Mikael Agricola publishes Abckiria.
- Lighthouse of Genoa completed in present form.
- The Japanese receive the first firearms from shipwrecked Portuguese.
- Indians in the Spanish Empire are declared free against the wish of local settlers.
- January 18 (baptized) – Alfonso Ferrabosco, Italian composer (d. 1588)
- January 31 – Tokugawa Ieyasu, Japanese shogun (d. 1616)
- February 16 – Kanō Eitoku, Japanese painter (d. 1590)
- February 18 – Charles III, Duke of Lorraine (d. 1608)
- April 1 – François de Bonne, duc de Lesdiguières, Constable of France (d. 1626)
- September 14 – Claudio Acquaviva, Italian Jesuit (d. 1615)
- November 8 – Lettice Knollys, Countess of Essex and later Countess of Leicester, lady-in-waiting to Elizabeth I of England (d. 1634)
- date unknown
- January 2 – Francesco Canova da Milano, Italian composer (b. 1497)
- January 3 – Juan Rodríguez Cabrillo, Portuguese explorer (b. 1499)
- January 9 – Guillaume du Bellay, French diplomat and general (b. 1491)
- February 21 – Ahmad ibn Ibrihim al-Ghazi, Imam of Adal (in battle) (b. c. 1506)
- March 6 – Baccio D'Agnolo, Florentine woodcarver (b. 1460)
- May 24 – Nicolaus Copernicus, mathematician and astronomer (b. 1473)
- July 19 – Mary Boleyn, mistress of Kings Francis I of France and Henry VIII of England (b. 1500)
- September 20 – Thomas Manners, 1st Earl of Rutland (b. 1492)
- November 29 – Hans Holbein the Younger, German artist, active in England
- December 27
- date unknown
- Palmer, Alan; Veronica (1992). The Chronology of British History. London: Century Ltd. pp. 147–150. ISBN 0-7126-5616-2.
- Bartl, Július. "1543". Slovak history: chronology & lexicon. Bolchazy-Carducci. p. 59. Retrieved 2013-02-11.
- Rowlett, Russ. "Lighthouses of Italy: Liguria". The Lighthouse Directory. University of North Carolina at Chapel Hill.