April 13 in history — What Happened Today in History

Beirut bus massacre: A confrontation between Phalangist paramilitaries and PLO militia marks the start of the 15-year Lebanese Civil War.

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.

Vietnam War: The Battle of An Lộc begins.

At 10:08 PM EST an oxygen tank aboard the Apollo 13 Service Module explodes, putting the crew in great danger and causing major damage to the Apollo command and service module (codenamed "Odyssey") while en route to the Moon.

At the Academy Awards, Sidney Poitier becomes the first African-American man to win the Best Actor award for the 1963 film Lilies of the Field.

The United States launches Transit 1-B, the world's first satellite navigation system.

CIA director Allen Dulles launches the mind-control program Project MKUltra.

In an ambush, 78 Jewish doctors, nurses and medical students from Hadassah Hospital, and a British soldier, are massacred by Arabs in Sheikh Jarrah. This event came to be known as the Hadassah medical convoy massacre.

World War II: German troops kill more than 1,000 political and military prisoners in Gardelegen, Germany.

World War II: Soviet and Bulgarian forces capture Vienna.

World War II: The discovery of mass graves of Polish prisoners of war killed by Soviet forces in the Katyń Forest Massacre is announced, causing a diplomatic rift between the Polish government-in-exile in London and the Soviet Union, which denies responsibility.

The Jefferson Memorial is dedicated in Washington, D.C., on the 200th anniversary of President Thomas Jefferson's birth.

A pact of neutrality between the USSR and Japan is signed.

A.E.K., a major Greek multi-sport club, is established in Athens by Greek refugees from Constantinople.

Jallianwala Bagh massacre: British Indian Army troops led by Brigadier-General Reginald Dyer kill approximately 379–1,000 unarmed demonstrators including men and women in Amritsar, India. Approximately 1,500 are injured.

The 31 March Incident leads to the overthrow of Sultan Abdul Hamid II.

The Colfax massacre: More than 60 to 150 black men are murdered in Colfax, Louisiana, while surrendering to a mob of former Confederate soldiers and members of the Ku Klux Klan.

The New York City Metropolitan Museum of Art is founded.

American Civil War: Raleigh, North Carolina is occupied by Union forces.

American Civil War: Union forces surrender Fort Sumter to Confederate forces.

Lajos Kossuth presents the Hungarian Declaration of Independence in a closed session of the National Assembly.

The Roman Catholic Relief Act 1829 gives Roman Catholics in the United Kingdom the right to vote and to sit in Parliament.

American Revolutionary War: American forces are ambushed and defeated in the Battle of Bound Brook, New Jersey.

George Frideric Handel's oratorio Messiah makes its world premiere in Dublin, Ireland.

The Sikh religion is formalised as the Khalsa – the brotherhood of Warrior-Saints – by Guru Gobind Singh in northern India, in accordance with the Nanakshahi calendar.

Samuel Argall, having captured Pocahontas in Passapatanzy, Virginia, sets off with her to Jamestown with the intention of exchanging her for English prisoners held by her father.

Samurai Miyamoto Musashi defeats Sasaki Kojirō in a duel at Funajima island.

Jordan Silk, Australian cricketer

Josh Gordon, American football player

Josh Reynolds, Australian rugby league player

Allison Williams, American actress and singer

Anderson, Brazilian footballer

Steven De Vuyst, Belgian politician

Lorenzo Cain, American baseball player

Anders Lindegaard, Danish footballer

Claudio Bravo, Chilean footballer

Hunter Pence, American baseball player

Nellie McKay, British-American singer-songwriter, musician, and actress

Ty Dolla Sign, American singer, songwriter, and musician

Kelli Giddish, American actress

Herb Trimpe, American author and illustrator (born 1939)

Ernesto Laclau, Argentinian-Spanish philosopher and theorist (born 1935)

Michael Ruppert, American journalist and author (born 1951)

Stephen Dodgson, English composer and educator (born 1924)

Cecil Chaudhry, Pakistani pilot, academic, and activist (born 1941)

Shūichi Higurashi, Japanese illustrator (born 1936)

John Archibald Wheeler, American physicist and academic (born 1911)

Muriel Spark, Scottish novelist, poet, and critic (born 1918)

Johnnie Johnson, American pianist and songwriter (born 1924)

Phillip Pavia, American painter and sculptor (born 1912)

Caron Keating, Northern Irish television host (born 1962)

Giorgio Bassani, Italian author and poet (born 1916)

Frenchy Bordagaray, American baseball player and manager (born 1910)