The onset of World War I in 1914 led to calls for the repeal of the eight-hour day and increased productivity. South Wales miners struck in 1915 and increased pay was demanded in 1916 resulting in the coalfields being put into state control. In 1914 the MFGB had joined with the National Union of Railwaymen (NUR) and the National Transport Workers' Federation (NTWF) in the Triple Alliance. In 1919 the Sankey Commission was set up to which the MFGB, colliery owners and government considered the future of the mining industry and two years later the government returned management of the collieries to their owners. In 1921 a decision by the NUR and NTWF not to strike in sympathy with the miners is remembered as Black Friday and signalled the end of the alliance.