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International Workers' Day, also known as May Day or Labour Day, is celebrated annually on 1 May to honor laborers, the labor movement, and the working class. Its origins trace back to the 1886 Haymarket affair in Chicago, a general strike for the eight-hour workday that turned violent, resulting in deaths and the controversial execution of four labor leaders. In 1889, the Second International in Paris officially designated 1 May as a day for international demonstrations, making it a yearly global event. While it is a public holiday in many countries, the United States and Canada instead celebrate Labor Day on the first Monday of September. In 1955, Pope Pius XII dedicated 1 May to Saint Joseph the Worker as a Catholic counterpoint to the communist celebrations. Interestingly, the movement was inspired by an earlier Australian stonemasons' strike in 1856, and the 1894 May Day riots further cemented its historical significance.