The founding of Labour Day is linked to events that took place in the United States in 1886. On 1 May, workers went on strike in Chicago to demand a shorter working day of 8 hours. Up until then, they had been working 15-20 hours a day and receiving meagre wages. The strike ended that day with many casualties. Similar rallies were organised in the US more than once, and in 1888, the congress of the American Federation of Labour in St Louis declared May 1 as the Day of the National Struggle for Workers' Rights.