Crusaders from the Fourth Crusade broke through Constantinople’s walls and entered the great city.
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Shapur I became co-emperor of the Sasanian Empire with his father Ardashir I.
Jonas Salk's Polio vaccine tested by Jonas Salk was given final approval by the US Food and Drug Administration.
Project Starshot was announced by Yuri Milner, Stephen Hawking, and Mark Zuckerberg.
Rock Around The Clock by Bill Haley and His Comets was recorded.
The Battle of Fort Sumter in South Carolina between the United States and the Confederate States started the American Civil War.