Shapur I became co-emperor of the Sasanian Empire with his father Ardashir I.
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Crusaders from the Fourth Crusade broke through Constantinople's walls and entered the great city.
The Battle of Fort Sumter in South Carolina between the United States and the Confederate States started the American Civil War.
Rock Around The Clock by Bill Haley and His Comets was recorded.
Project Starshot was announced by Yuri Milner, Stephen Hawking, and Mark Zuckerberg.
The 'Twentieth Century Dinosaurs' exhibit opened at the Smithsonian Institution Museum of Natural History.
