May the 1st
The first day of the month of May is known as May Day. In Britain, as in most parts of Western Europe, May day marked the end of the harsh winter months.
Traditional May Day celebrations included dancing around maypoles:
Two other celebrations:
May 1st 1707: The Kingdom of Great Britain established
The act of union between Scotland and England came into force. Scottish church bells played the tune "Why am I so sad on my wedding Day" because the Union was brought about in spite of opposition by the majority of Scots.
May 1st 1931: Empire State Building opened to the public.