Historical Events
- Milwaukee Braves future Baseball Hall of Fame pitcher Warren Spahn beats NY Mets, 6-1 for his 328th win; most by a left-hander in MLB history
Catholic Encyclical
Pope John XXIII publishes encyclical "Pacem in terris", that peace between all peoples must be based on truth, justice, love and freedom

John XXIII
- US performs nuclear test at Nevada Test Site
Famous Birthdays
- Billy Bowden, New Zealand cricket umpire (84 Tests, 200 ODIs, 24 T20Is), born in Auckland, New Zealand
- Chris Ferguson, American professional poker player, born in Los Angeles, California
- Eddy Moya, actor, born in El Paso, Texas
- Elizabeth Smylie, tennis star (1987 Oklahoma City), born in Perth, Australia
1963 Highlights
About April 11, 1963
Day of the Week: Thursday
How Long Ago? 57 years, 9 months and 16 days
Leap Year: No
Generation Baby Boomer
Chinese Zodiac: Rabbit
Star Sign: Aries