Labour Day (1 May)International Workers’ Day

In paganism times in West Europe and British islands the 1 May was a holiday
spring sowing.
He was dedicated to the sun god and fertility Belene, which brings the symbolic sacrifice Druids, Celtic priests.

May 1, 1886 socialist, communist and anarchist organizations in the U.S. and Canada organized a series of rallies and demonstrations. In the dispersal of a demonstration in Chicago on May 4 killing six demonstrators. In the ensuing mass protests against police brutality in a bomb blast followed a firefight killed eight policemen and at least four workers (according to some estimates, up to fifty dead and wounded ), several dozen people were injured. On charges of bombing four workers anarchists were sentenced to death by hanging (later it was proved that the accusation was false). It is in memory of the executed II International Congress of Paris (July 1889) announced on 1 May Day solidarity of workers around the world and suggested that the annual observance of his demonstrations with the social demands

Russia/USSR
The first 1 May was in 1890 in Warsaw. After October revolution this day was official. In the May Day workers of the USSR «express their solidarity with the revolutionary struggle of the working people of the capitalist countries, the national liberation movement, are determined to give everything for peace and for the building of a communist society»
May 1, 1990 the last time the official May Day demonstration.

In 1992, the festival was renamed the " Day Labour and Spring ".
Today it is a celebration is 86 counties.