The United States Environmental Protection Agency was formed in the US under Director William Ruckelshaus.
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Paleoanthropologist Louis Leakey discovered a 1.4 million-year-old Homo erectus in Olduvai Gorge, Tanzania.
The Battle of Tirad Pass was fought.
Sweden introduced a groundbreaking Freedom of Press Act, becoming the first nation to introduce freedom of speech.
The world's first self-sustaining nuclear chain reaction happened in Chicago Pile-1 at the University of Chicago. It was overseen by Enrico Fermi.
The Chinese child Emperor Pu Yi ascended the Chinese throne at the age of two.