International Workers' Day. Also known as "51", set in the annual May 1. It is a world-class production team, working people in the common festival. May 1 International Labor Day originated from the U.S. city of Chicago workers strike. May 1, 1886, Chicago, more than 216,000 workers to fight for implementation of eight hour working day and held a general strike, after a bloody struggle, and finally get a victory. To commemorate this great labor movement, in July 1889 Second International announced the annual May 1 as International Labor Day. The decision immediately workers around the world with a positive response. May 1, 1890, Europe and the United States to take the lead in the streets of the working class, held a grand demonstration and assembly, for the legitimate rights and interests. From then on, every day all over the world to the working people of assembly, of procession, in celebration.