Thursday May 1st, Mexico and most of the world celebrates Labor Day. The U.S. doesn’t as the celebration was a result of The Haymarket Riot in Chicago in 1886. Workers were striking for an eight-hour workday and an unknown person threw a dynamite bomb at the police ensuing retaliatory gunfire.
The Haymarket affair is generally considered significant as the origin of International Workers’ Day held on May 1. It was also the climax of the period of social unrest among the working class in the U.S. known as the Great Upheaval. (Thank you Wikipedia).
There will be commemorative parades in most cities in Mexico.