1820

1820 (MDCCCXX) was a leap year starting on Saturday in the Gregorian calendar and a leap year starting on Thursday in the Julian calendar.

 Events 
 Venus de Milo is discovered.
 Hans Christian Ørsted discovers the relationship between electricity and magnetism.
 Births 
 March 22 – John Brown, English cricketer (died 1893)
 May 12 – Florence Nightingale, Italian-born English nurse (died 1910)
 date unknown
 Anne Bronte, English novelist (died 1849)
 King Victor Emmanuel II of Italy (died 1873)
 Joseph Whitaker, English publisher (died 1896)

 Deaths 
George III of the United Kingdom (b. 1738)
Daniel Boone (b. 1734)

 Books 
 The Sketch Book of Geoffrey Crayon, Gent. by Washington Irving