The Road Less Travelled
1918-1920: David Lloyd George (National Liberal)
1918 (National Coupon with Conservatives and National Democrats) def. Andrew Bonar Law (National Coupon --- Conservative), Eamon de Valera (Sinn Fein), William Adamson (Labour), H.H. Asquith (Liberal), George Nicoll Barnes (National Coupon --- National Democrat)
1920-1926: Austen Chamberlain (National Conservative)
1921 (National Coupon with National Democrats and 'Mondite' National Liberals) def. J.R. Clynes (Labour), Winston Churchill (Unionist Coupon --- Unionist Conservative), George Nicoll Barnes (National Coupon --- National Democrat), H.H. Asquith (Liberal), Alfred Mond (National Coupon --- 'Mondite' National Liberal), David Lloyd George (Unionist Coupon --- 'Lloyd Georgeite' National Liberal)
1926-1931: Ramsay MacDonald (Labour)
1926 (Majority) def. Austen Chamberlain (National Coupon --- National Conservative), David Lloyd George (Liberal), Alfred Mond (National Coupon --- National Liberal), Winston Churchill (Unionist), Albert Inkpin (Communist)
1931-1940: Oswald Mosley (National)
1931 (Majority) def. Arthur Henderson (Labour), David Lloyd George (Liberal), Winston Churchill (Unionist), Harry Pollitt (Communist)
1936 (Majority) def. Arthur Greenwood (Labour), Winston Churchill (Unionist), Phillip Sassoon (Liberal)
1940-????: Anthony Eden ('War' National leading War Government with Labour, Unionists, and Liberals)
Lloyd George's government falls apart over the conduct of the war in Ireland. Austen Chamberlain manages to cobble together a continuity government that manages to win a horrendously split election in 1921. The strident unionists under Churchill refuse to participate in Chamberlain's government. Over the next few years, the parties slowly coalesce again. Barnes and most of the National Democrats are absorbed into Mond's National Liberals, or are defeated by Labour. Lloyd George manages to unseat Asquith and become leader of the Liberals proper. Churchill's Unionists suffer as many of his party's MPs choose to rejoin the National Conservatives.
Chamberlain has the poor luck of his parliamentary term expiring in 1926 during a General Strike. His attempts to forestall the election are shot down. The General Strike is less severe as economic conditions are slightly better, and Labour win a majority. The Liberals and Communists enjoy a surge, while Churchill is punished by his strident anti-trade unionism. In Opposition, the parties of the National Coupon merge as the National Party, the 20th century incarnation of Toryism. And under a new leader, who has radical propositions to reform the economy, the constitution and the diplomatic face of Europe...
MacDonald proves a disappointment as the ensuing Great Depression leads to austerity and when the decision is made to make cuts to welfare, his Cabinet rebels. The King's advice to form a national government falls on deaf ears to Mosley, who goes on to win in a landslide. The Liberals manage to cling on to many seats they won in 1926, while the Unionists suffer further, though Mosley's radicalism means many traditionalists are looking at the Unionists with sympathy.
Mosley's dynamic policies prove popular and he is rewarded with a larger majority in 1936, winning his seats mostly from Labour, while the Unionists win seats in rural, Scottish and Welsh seats, with the Liberals coming out the worst. The Communists are reduced to two seats. However, the latter half of Mosley's time in office is concerned with the rise of fascism in Europe, and Mosley grows increasingly unpopular as he does his utmost to avoid war, while allowing the Germans and Italians to take ever greater liberties in territorial aggrandisement. The National Party ultimately splits, with Anthony Eden leading a gang of backbench rebels to call a vote of no confidence in Mosley, and forms a National Government with Labour, Churchill and the Liberals. Mosley is still leader of a rump 'Peace' National Party and is Leader of the Opposition, lamenting the country's descent into war.