The people of Wales were generally supportive of the monarchy (when George V came to the throne in 1910, one of the first acts was to change his family name from the German Saxe-Coburg to the English Windsor). Many thousands of her soldiers answered the call to fight for Britain during the World War I that began in 1918. Before the war had ended, some 40,000 South Wales miners had joined the armed forces "to protect their homes against the barbaric forces of the Hun."

Welsh participation in the "War to end all Wars," was certainly aided by the immense popularity of its native son Lloyd George, the so-called "Welsh Wizard," who rose to astronomical heights, ultimately becoming Prime Minister in 1916, presiding over a coalition government. His enthusiasm for the great cause against the evil that was Germany swept away any religious disposition the people of Wales may have harboured to stay out of the imperial conflict.

There was another effect upon Wales, however, entirely unanticipated at first. Welsh solders played significant roles in the great battles of the Somme and Ypres. By suffering alongside their fellows from all parts of the British Isles, Welsh soldiers began to feel less Welsh and more British, less provincial, less "different." There was a growth in national consciousness that received an enormous impact from the Conscription Bill of 1916, and by the end of the war more that 280,000 Welshmen had served some time in the armed forces.

Not all the people of Wales supported the government. Attempts at producing more coal at no increase in pay led to a strike in the South Wales coalfield in the summer of 1916. The enormous increase in coal industry profits was not being passed on to the miners, who naturally wished to have their share. Over two hundred thousand miners in Britain refused to be intimidated by the Munitions of War act that made striking a criminal offence. In Scotland, in displays of solidarity with their fellow workers in the rest of Britain, striking shipyard workers caused so much discontent that the area around Glasgow became known as "Red Clyde" to signify communist infiltration of the trade unions.

Similar conflicts in South Wales, however, where the importance of coal to the British war effort cannot be underestimated, made the miners confident of victory in their fight with the coal owners. Lloyd George himself came to Cardiff to meet the miners, assuring them that the owners would honour the agreement between the government and the Miners' Federation.

It wasn't just the horrors of the "War to end all Wars" that affected almost everyone in Britain, for the nation was particularly hard hit by the continuation of the Great Depression. Its industries had not kept pace with the rapid growth in other nations, especially the newly emerging ones. There was too much reliance on the old traditional methods of mining, shipbuilding, cotton manufacture, etc, all of which were now finding it difficult, if not impossible, to compete in world markets. They were also hampered by lack of investment capital and failure to adapt too more efficient, modern methods. A great slump left millions of British workers unemployed.

It was Labour, with its working class M.P.'s who now took the lead in advocating increased social security measures. These included a national minimum wage, the nationalization of basic industries such as coal, railways, and electricity, and the imposition of higher taxes to pay for social welfare and the reduction of the National Debt. The introduction of the "dole" (unemployment benefits) allowed workers to keep their families and homes together while unemployed.

Labour formed its first government in 1924 under James Ramsey MacDonald. Unable to solve the nation's problems, it was quickly followed by the Conservatives under Stanley Baldwin, equally inept at handling the major crises of the nation. Iron, steel, coal, cotton and shipbuilding suffered the most, the very industries that Britain's free trade economy relied upon to provide the bulk of the consumer and capital goods exported to provide for the large imports of food and raw materials. South Wales was the home of three of these major industries. The great General Strike began in 1926. It was only settled when the owners who were able to demand longer hours and less pay had worn down the resistance of the miners.

To help alleviate the miserable conditions in the industrial areas of Britain, the Conservative government of Stanley Baldwin undertook a modest program of social reform to appease working class opinion. The Widows, Orphans, and Old Age Health Contributory Pensions schemes extended the Act of 1911 and insured over 20 million people.

New health measures, aided by the import of cheap nutritious food from the US (such as canned beans), led to a marked increase in population, accompanied by a building boom. Old industries were replaced by newer ones, including the manufacture of bicycles, automobiles, electrical goods and chemicals, mostly located in the south-eastern and midland counties of England.

Very few of the changes reached south Wales, where the repercussions of huge losses in the coal industry have never dissipated. Massive emigration took place from the Welsh Valleys, where ironically, the way was paved for a renaissance in Welsh nationalism, a resurgence of the spirit of Welshness. Most of the industrialists and coal mine owners, shipping magnates and building barons who made their fortunes in Wales were English or Scottish, people viewed as outsiders and foreign, even to those whose language had now been mainly replaced by English.