May 1, International Labor Day, is a historical commemoration of the struggle of the working class all over the world, and every country attaches great importance to it. 1894, Congress officially designated Labor Day as a legal holiday. Socialist countries designated May 1 day as Labor Day, so it was called May Day.

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Labor Day originated in America in the19th century. A carpenter named mcguire founded the predecessor of the AFL-CIO.

1882, he suggested that the "Central Trade Union" in new york should praise their contributions to American workers. With the support of the Knights of Labor, 10,000 workers marched in new york on September 5th, which was designated as "Labor Day".

1884, the Knights of Labor changed the first Monday in September to Labor Day.

1894, Congress officially designated Labor Day as a legal holiday.