Emperor Constantius II was baptized on his deathbed hours before passing.
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Explorer Christopher Columbus, on his second voyage, found Dominica and the Kalinago people.
Queen Elizabeth II inaugurated the flow of oil from the UK's first-ever oil pipeline.
NASA launched the last space probe in the Mariner Program, Mariner 10.
The Soviet Union sent a dog into space aboard the spacecraft Sputnik II.
The parliament of England passed the first Act of Supremacy, granting the monarch complete control of the Church of England.
