Overview
A progressive alliance in the UK is the idea of a cross-party political alliance supporting "progressive politics", generally in opposition to right-wing parties, chiefly the Conservative Party.
History
20th century
The term progressive alliance has been used to describe the Gladstone–MacDonald pact, the 1903 agreement between the Liberal Party and the Labour Representation Committee (forerunner to the Labour Party) to stand aside for each other in constituencies.
In the 1930s, the movement for a Popular Front called for a broad anti-fascist alliance involving Labour, the Liberals, the Communists and anti-fascist Conservatives. This policy was strongly supported by the Communist Party, whilst supporters of the Popular Front such as Stafford Cripps achieved a significant degree of influence within the Labour Party at this time, particularly after the outbreak of the Spanish Civil War in 1936; however, the Labour Party Conference voted against a Popular Front policy on several occasions.
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