coalminers' strike was a key factor in destroying support for the Liberal party in south Wales. [ 81 ] The industrial workers of Wales began shifting towards a new political organisation, established by Hardie and others to ensure an elected representation for the working class, which is now called the Labour party. [ 82 ] When in 1908 the Miners' Federation of Great Britain became affiliated to the Labour Party the four Labour candidates sponsored by miners were all elected as MPs. [ 82 ] By 1922, half of the Welsh seats in Westminster were held by Labour politicians, which was the beginning of a Labour hegemony which would dominate Wales into the 21st century. [ 82 ] Despite economic growth in the first two decades of the 20th century, from the early 1920s to the late 1930s, Wales' staple industries endured a prolonged slump, leading to widespread unemployment and poverty in the South Wales valleys. [ 83 ] For the first time in centuries, the population of Wales went into decline; the scourge of unemployment only relented with the production demands of the Second World War . [ 84 ] The Second World War (1939–1945) saw Welsh servicemen and women fight in all the major theatres of war, with some 15,000 of them killed. [ 85 ] Bombing raids brought major loss of life as the German Air Force targeted the docks at Swansea , Cardiff and Pembroke . [ 85 ] After 1943, 10% of Welsh conscripts aged