Labour Day in USA and Canada is held on the first Monday of September each year. Whereas most of the rest of the world celebrate it on the first Monday in May. So why it is different to the rest of the world?

Encylopidea Britannica writes:

In 1889 an international federation of socialist groups and trade unions designated May 1 as a day in support of workers, in commemoration of the Haymarket Riot in Chicago (1886). Five years later, U.S. Pres. Grover Cleveland, uneasy with the socialist origins of Workers’ Day, signed legislation to make Labor Day—already held in some states on the first Monday of September—the official U.S. holiday in honour of workers.

Canada followed suit not long afterward. After this incident in 1886 May Day became an international holiday celebrated by workers and radicals across the world. It held particular significance in socialist countries like China, Cuba and the Soviet Union where the day is usually celebrated with big parades.

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