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.
The world's first person visited space.
Israeli Knesset chose April 13 as the official Holocaust Remembrance Day.
Project Starshot was announced by Yuri Milner, Stephen Hawking, and Mark Zuckerberg.
The first Space Shuttle mission was launched.
