March 20 is the 79th day of the year in the Gregorian Calendar (80th in Leap years). There are 286 days remaining.
- 1413 - Henry V becomes King of England
- 1602 - The Dutch East India Company is established.
- 1739 - Nadir Shah occupies Delhi in India and sacks the city stealing the jewels of the Peacock Thrown[?].
- 1760 - The "Great Fire" of Boston destroyers 349 buildings.
- 1815 - Napoleon enters Paris after escaping from Elba with a regular army of 140,000 and a volunteer force of around 200,000 beginning his "Hundred Days" rule.
- 1848 - King Ludwig I of Bavaria abdicates
- 1852 - Harriet Beecher Stowe's Uncle Tom's Cabin is published
- 1899 - At Sing Sing[?] prison, Martha M. Place[?] becomes the first woman executed in an electric chair.
- 1913 - Sung Chiao-jen, a founder of the Chinese nationalist party (KMT), is wounded in an assassination attempt and dies 2 days after.
- 1914 - In New Haven, Connecticut the first international figure skating championship takes place.
- 1922 - The USS Langley is commissioned as the first United States Navy aircraft carrier.
- 1933 - Dachau, the first Nazi concentration camp, is completed
- 1952 - The United States Senate ratifies a peace treaty[?] with Japan.
- 1956 - Tunisia gains independence from France
- 1964 - The precursor of the European Space Agency, ESRO[?] (European Space Research Organization) is established per an agreement signed on June 14, 1962.
- 1976 - Patty Hearst is found guilty of armed robbery of a San Francisco Bank.
- 1985 - Libby Riddles[?] becomes the first women to win the 1,135-mile Iditarod dog sled[?] race.
- 1987 - The Food and Drug Administration approves anti-AIDS drug AZT.
- 1990 - Ferdinand Marcos's widow, Imelda Marcos[?], goes on trial for bribery, embezzlement, and racketeering[?].
- 1995 - Terrorist incident: Members of the Aum Supreme Truth release sarin gas in the Tokyo on five separate subway trains killing 12 and injuring around 5,500.
- 1996 - In Los Angeles, California, Erik and Lyle Menendez[?] are found guilty of first-degree murder for the shotgun killing of their parents.
- 2000 - Jamil Abdullah Al-Amin[?], a former Black Panther, is captured after gun battle that left a sheriff's deputy dead.
- 2003 - 2003 invasion of Iraq: The United States and three other countries invade Iraq.
- 43 BC - Ovid, poet (+ 17/18)
- 1770 - Friedrich Hölderlin, German poet, novelist, and dramatist (+ 1843)
- 1811 - Napoleon II of France (+ 1832)
- 1823 - Ned Buntline[?], "dime novelist", publisher, writer, publicist (+ 1886)
- 1828 - Henrik Ibsen, playwright and dramatist (+ 1906)
- 1856 - Frederick W. Taylor, inventor, efficiency expert
- 1874 - Börries von Münchhausen[?], poet (+ 1945)
- 1890 - Beniamino Gigli, tenor (+ 1957)
- 1890 - Lauritz Melchior, opera singer (+ 1973)
- 1904 - B. F. Skinner, behavioral psychologist (+ 1990)
- 1906 - Ozzie Nelson[?], actor, band leader (+ 1975)
- 1908 - Sir Michael Redgrave, actor (+ 1985)
- 1915 - Rudolf Kirchschläger[?], Austrian President (+ 2000)
- 1917 - Dame Vera Lynn[?], actress, singer
- 1921 - Rudolf Noelte[?], film director (+ 2002)
- 1921 - Sister Rosetta Tharpe[?], singer (+ 1973)
- 1922 - Carl Reiner, director, producer, actor, comedian
- 1928 - Fred Rogers, children's television host (+ 2003)
- 1934 - Willie Brown[?], mayor of San Francisco, California
- 1937 - Jerry Reed[?], country musician
- 1939 - Brian Mulroney, eighteenth Prime Minister of Canada
- 1948 - Bobby Orr, ice hockey player
- 1950 - William Hurt, actor
- 1958 - Holly Hunter, actress
- 1957 - Spike Lee, film director, actor
- 1964 - Natacha Atlas, Belgian singer
- 1964 - Tracy Chapman, musician
- 1974 - Carsten Ramelow, football player, National Team of Germany
- 1974 - Paula Garces[?], actress
- 1976 - Chester Bennington, musician ("Linkin Park")
March 19 - March 21 - February 20 - April 20 -- listing of all days
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