Hillary Clinton announced her candidacy for US President.
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Project Starshot was announced by Yuri Milner, Stephen Hawking, and Mark Zuckerberg.
The world's first person visited space.
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.
Shapur I became co-emperor of the Sasanian Empire with his father Ardashir I.
