* 1111 – Henry V is crowned Holy Roman Emperor.
* 1204 – Constantinople falls to the Crusaders of the Fourth Crusade, temporarily ending the Byzantine Empire.
* 1250 – The Seventh Crusade is defeated in Egypt, Louis IX of France is captured.
* 1256 – The Grand Union of the Augustinian order formed when Pope Alexander IV issues a papal bull Licet ecclesiae catholicae.
* 1598 – Henry IV of France issues the Edict of Nantes, allowing freedom of religion to the Huguenots. (Edict repealed in 1685.)
* 1742 – George Frideric Handel's oratorio Messiah makes its world-premiere in Dublin, Ireland.
* 1796 – The first elephant ever seen in the United States arrives from India.
* 1829 – The British Parliament grants freedom of religion to Roman Catholics.
* 1849 – Hungary becomes a republic.
* 1861 – American Civil War: Fort Sumter surrenders to Confederate forces.
* 1868 – The Abyssinian War ends as British and Indian troops capture Magdala.
* 1870 – The Metropolitan Museum of Art founded.
* 1873 – The Colfax Massacre takes place.
* 1902 – James C. Penney opens his first store in Kemmerer, Wyoming.
* 1919 – The Establishment of the Provisional Government of the Republic of Korea.
* 1919 – Jallianwala Bagh massacre: British troops massacre at least 379 unarmed demonstrators in Amritsar, India. At least 1200 wounded.
* 1919 – Eugene V. Debs enters prison at the Atlanta Federal Penitentiary in Atlanta, Georgia, for speaking out against the draft during World War I.
* 1921 – Foundation of the Spanish Communist Workers' Party.
* 1939 – In India, the Hindustani Lal Sena (Indian Red Army) is formed and vows to engage in armed struggle against the British.
* 1941 – Pact of neutrality between the USSR and Japan is signed.
* 1943 – World War II: The discovery of a mass grave of Polish prisoners of war executed by Soviet forces in the Katyń Forest Massacre is announced, alienating the Western Allies, the Polish government in exile in London, from the Soviet Union.
* 1943 – James Boarman, Fred Hunter, Harold Brest and Floyd G. Hamilton take part in an attempt to escape from Alcatraz .
* 1943 – The Jefferson Memorial is dedicated in Washington, D.C., on the 200th anniversary of Thomas Jefferson's birth.
* 1944 – Diplomatic relations between New Zealand and the Soviet Union are established.
* 1945 – German troops kill more than 1,000 political and military prisoners in Gardelegen Germany.
* 1945– Ninth American army crosses The Elbe River in Germany
* 1948 – The Hadassah medical convoy massacre: In an ambush, 79 Jewish doctors, nurses and medical students from Hadassah Hospital and a British soldier are massacred by Arabs in Sheikh Jarra near Jerusalem.
* 1953 – CIA director Allen Dulles launches the mind-control program MKULTRA.
* 1958 – Van Cliburn is the first American to win the Tchaikovsky Competition in Moscow.
* 1963 – At the Academy Awards, Sidney Poitier becomes the first African-American male to win the Best Actor award for Lilies of the Field.
* 1969 – Closure of the Brisbane tramway network.
* 1970 – An oxygen tank aboard Apollo 13 explodes, putting the crew in great danger and causing major damage to the spacecraft while in route to the Moon.
* 1972 – The Universal Postal Union decides to recognize the People's Republic of China as the only legitimate Chinese representative, effectively expelling the Republic of China administering Taiwan.
* 1974 – Western Union (in cooperation with NASA and Hughes Aircraft) launches the United States' first commercial geosynchronous communications satellite, Westar 1.
* 1975 – Bus Massacre in Lebanon: Attack by the Phalangist resistance kill 26 militia members of the P.F.L. of Palestine, marking the start of the 15-year Lebanese Civil War.
* 1976 – The United States Treasury Department reintroduced the two-dollar bill as a Federal Reserve Note on Thomas Jefferson's 233rd birthday as part of the United States Bicentennial celebration.
* 1983 – Harold Washington is elected as the first African-American mayor in Chicago's history.
* 1984 – India moves into Siachen Glacier thus annexing more territory from the Line of Control.
* 1987 – Portugal and the People's Republic of China sign an agreement in which Macau would be returned to China in 1999.
* 1992 – The Great Chicago Flood.
* 1997 – Tiger Woods becomes the youngest golfer to win The Masters Tournament.

Notable Births/Deaths - to me anyway

1743 – Thomas Jefferson, 3rd President of the United States (d. 1826)
1962 – Hillel Slovak, Israeli-born guitarist (d. 1988)
1961 – Hiro Yamamoto, American rock bassist