July 1, 1867. The Constitution Act, 1867 is enacted, uniting the three separate colonies of the Province of Canada, Nova Scotia, and New Brunswick into a single Dominion within the British Empire called Canada.
May 1, 1960. An American U-2 spy plane piloted by Francis Gary Powers was shot down over Central Russia. Powers was tried, convicted and sentenced to 10 years in prison, but was released in exchange for an imprisoned Soviet spy.
May 4, 1886. The Haymarket Square Riot occurred in Chicago after 180 police officers advanced on 1,300 persons gathered in the square listening to speeches of labor activists and anarchists. An incendiary device thrown by an unknown person caused police to open fire and led to the death of several people, including eight policemen.