Today it is rarely remembered that federalism was one of the key intellectual strands in Britain before the start of the European integration after the Second World War. At its peak, in 1940 and 1941, the Federal Union, the most important association advocating federalism in Britain, had 12 000 members. Federalists included notable Labour and Conservative party members alike and they sought to have as many federalist-oriented MPs in Parliament as possible.
Parliament was in many ways the focal point of the British federalism discussion due to its position of power, publicity, prestige and government vs. opposition politics. Its debates on federalism related to foreign policy and positioning towards the Soviet Union with hostilities against Western European co-operation. They featured not only the difficult economic situation and the reconstruction of the continental Western Europe but also the efforts to redefine the British role in international affairs.
Previous research has mainly focused on movements and associations who advocated federalism in Britain. Our emphasis, however, will be on arguments presented for and against European federalism in the Westminster parliament. Newspapers and archival sources are used to complement the analysis to reconstruct the understanding of European federalism as a political ideology and concept. We ask, for example, as what kind of alternative the idea of federal Europe was presented? Who were its main proponents in the British Parliament? And, what was the turning point for the decline of federalist thought in Britain according to the parliamentary debates?
