Ferie secolare : Chicago, Saturday May 1st, 1886: 350,000 workers go on strike to call for an 8-hour working day. Industries are paralyzed nationwide. On Monday, as demonstrations go on, the police open fire. On Tuesday, Chicago is again on strike. Following a bomb launched against them, the police shoot again. 12 dead, of which 7 policemen. 8 anarchists will be condemned and executed. In 1889, the Socialist International Movement met in Paris and declared this day international workers' day . The Soviets will follow suit, just as the Nazis. In France, under the Vichy regime (1940-1944), the celebration is renamed Labour Day .