Wikipedia:Selected anniversaries/May 1
May 1: Beltane in Ireland and Scotland, May Day in various countries.
- 1707 - The Kingdoms of England and Scotland merged to form the Kingdom of Great Britain, a single kingdom encompassing the entire island of Great Britain with a single parliament and government based in Westminster.
- 1840 - The Penny Black (pictured), the first official adhesive postage stamp, was issued in the United Kingdom.
- 1893 - The World's Columbian Exposition, a World's Fair to celebrate the 400th anniversary of the discovery of the New World by Christopher Columbus, opened in Chicago, United States.
- 1956 - A doctor in Japan reported an "epidemic of an unknown disease of the central nervous system", marking the official discovery of Minamata disease.
- 1960 - Bombay State, India was partitioned into Gujarat and Maharashtra along linguistic lines.