- 1606 – The Union Jack is adopted as the national flag of Great Britain.
- 1861 – The American Civil War begins as Confederate forces fire on Fort Sumter.
- 1937 – The first aircraft jet engine is successfully tested. Sir Frank Whittle invented and tested the engine, only a few months before German engineer Hans von Ohain ran his jet engine, which was to power the first ever all-jet aircraft.
- 1955 – The polio vaccine, developed by Dr. Jonas Salk, is declared safe and effective.
- 1961 – Russian cosmonaut Yuri Gagarin became the first human in space. He traveled aboard the Soviet spacecraft Vostok I to an altitude of 187 miles (301 kilometers) above the earth and completed a single orbit in a flight lasting 108 minutes. The spectacular Russian success intensified the already ongoing Space Race between the Russians and Americans. Twenty-three days later, Alan Shepard became the first American in space. This was followed in 1962 by President Kennedy’s open call to land an American on the moon before the decade’s end.
- 1981 – The first space shuttle flight occurred with the launching of Columbia with astronauts John Young and Robert Crippen aboard. Columbia spent 54 hours in space, making 36 orbits, then landed at Edwards Air Force Base in California.
- 1988 – “The Last Emperor” receives nine Academy Awards. Bernardo Bertolucci’s biopic about Puyi, the last Emperor of China, was the first film to be awarded all the Oscars it was nominated for.
- 1577 – Christian IV (King of Denmark for 59 years)
- 1823 – Alexander Ostrovsky (Russian playwright)
- 1871 – Ioannis Metaxas (Greek general, politician, 130th Prime Minister of Greece)
- 1940 – Herbie Hancock (American pianist, composer, bandleader)
- 1947 – Tom Clancy (American author)
- 1947 – David Letterman (Talk Show Host)
- 1950 – David Cassidy (Singer and actor)
- 1956 – Andy Garcia (Actor)
- 1957 – Vince Gill (Singer)
- 1979 – Claire Danes (Actress)
- 1555 – Joanna of Castile
- 1945 – Franklin D. Roosevelt (American politician, 32nd President of the United States)
- 1975 – Josephine Baker (American/French actress, singer, dancer)
- 1981 – Joe Louis (American boxer)
- 1989 – Sugar Ray Robinson (American boxer)