<P> In 1864, the eight - hour day quickly became a central demand of the Chicago labour movement . The Illinois legislature passed a law in early 1867 granting an eight - hour day but had so many loopholes that it was largely ineffective . A citywide strike that began on 1 May 1867 shut down the city's economy for a week before collapsing . </P> <P> On 25 June 1868, Congress passed an eight - hour law for federal employees which was also of limited effectiveness . It established an eight - hour workday for labourers and mechanics employed by the Federal Government . President Andrew Johnson had vetoed the act but it was passed over his veto . Johnson told a Workingmen's party delegation that he couldn't directly commit himself to an eight - hour day, he nevertheless told the same delegation that he greatly favoured the "shortest number of hours consistent with the interests of all ." According to Richard F. Selcer, however, the intentions behind the law were "immediately frustrated" as wages were cut by 20% . </P> <P> On 19 May 1869, President Ulysses Grant issued a National Eight Hour Law Proclamation . </P> <P> In August 1866, the National Labor Union at Baltimore passed a resolution that said, "The first and great necessity of the present to free labour of this country from capitalist slavery, is the passing of a law by which eight hours shall be the normal working day in all States of the American Union . We are resolved to put forth all our strength until this glorious result is achieved ." </P>

When was the eight hour work day established