17 April History
- 858 - Benedict III ends his reign as Catholic Pope.
- 1492 - Christopher Columbus signs a contract with Spain to find a western route to the Indies.
- 1521 - Martin Luther is excommunicated from the Roman Catholic Church.
- 1524 - Present-day New York Harbor is discovered by Giovanni Verrazano.
- 1535 - Antonio Mendoza is appointed first viceroy of New Spain.
- 1758 - Frances Williams, the first African-American to graduate for a college in the western hemisphere, publishes a collection of Latin poems.
- 1808 - Bayonne Decree by Napoleon I of France orders seizure of U.S. ships.
- 1824 - Russia abandons all North American claims south of 54' 40'.
- 1861 - Virginia become eighth state to secede from the Union.
- 1864 - General Grant bans the trading of prisoners.
- 1865 - Mary Surratt is arrested as a conspirator in the Lincoln assassination.
- 1875 - The game "snooker" is invented by Sir Neville Chamberlain.
- 1895 - China and Japan sign peace treaty of Shimonoseki.
- 1929 - Baseball player Babe Ruth and Claire Hodgeson, a former member of the Ziegfield Follies, get married.
- 1946 - The last French troops leave Syria.
- 1947 - Jackie Robinson bunts for his first major league hit.
- 1961 - Some 1,400 Cuban exiles attack the Bay of Pigs in an attempt to overthrow Fidel Castro.
- 1964 - Jerrie Mock becomes first woman to fly solo around the world.
- 1969 - Sirhan Sirhan is convicted of assassinating Senator Robert F. Kennedy.
- 1970 - Apollo 13–originaly scheduled to land on the moon–lands back safely on Earth after an accident.
- 1975 - Khmer Rouge forces capture the capital of Cambodia, Phnom Penh.
- 1983 - In Warsaw, police rout 1,000 Solidarity supporters.
17 April Birthdays
- 1622 - Henry Vaughan, poet
- 1676 - Frederick I, king of Sweden
- 1741 - Samuel Chase, signer of the Declaration of Independence
- 1820 - Alexander Cartwright, sportsman, developed baseball.
- 1866 - Ernest Henry Starling, British physiologist.
- 1885 - Isak Dinesen (Karen Dinesen), Danish writer (Out of Africa).
- 1894 - Nikita S. Khrushchev, Soviet premier (1958-64).
- 1897 - Thornton Wilder, novelist and playwright (Our Town).
- 1923 - Harry Reasoner, American broadcast journalist.
- 1928 - Cynthia Ozick, writer (The Cannibal Galaxy, The Messiah of Stockholm).