Today, Friday 1st May, is May Day, a global celebration of working people supported and promoted by the international trade union movement. The first Monday in May is a public holiday in honour of Irish working people and was established in 1994, but the roots of May Day run much deeper.
The 1904 Conference of the Second International called on "all Social Democratic Party organisations and trade unions of all countries to demonstrate energetically on the First of May for the legal establishment of the eight hour day, for the class demands of the proletariat, and for universal peace."
The date was chosen to commemorate the Haymarket affair, the events that surrounded and followed a May 1886 union demonstration at Haymarket Square in Chicago.
At its national convention in Chicago, held in 1884, the Federation of Organized Trades and Labor Unions (which later became the American Federation of Labor), had proclaimed that "eight hours shall constitute a legal day's labor from and after May 1, 1886.”
Up to this point working conditions were severe and it was quite common to work up to 16 hours a day in unsafe conditions. Death and injury were commonplace in many workplaces.
On 1st May 1886 more than 300,000 workers from 13,000 businesses across the US walked off their jobs in the first May Day celebration in history. In Chicago, 40,000 went out on strike.
The demonstration at Haymarket Square began as a peaceful rally in support of the eight-hour work day. The previous day police had killed eight workers when they fired into the crowds at the McCormick Reaper Works.
On 4th May at Haymarket Square, a bomb was thrown into the police ranks killing police officer Mathias J. Degan. An estimated seven or eight civilians died, and up to 40 were wounded.
The trial of eight protesters that followed is widely regarded as a miscarriage of justice. Four of them were executed in 1887. The remaining organisers were pardoned six years later.
The May Day movement spread across the industrialised world and is now celebrated as an official workers' holiday in 66 countries across the globe.
For more on the history of May Day and the Haymarket Affair visit the Industrial Workers of The World website and see also The Bloody Story of How May Day Became a Holiday for Workers (Time Magazine, 1st May 2018)