From 1918 to the late 1940s, a host of influential scientists and intellectuals in Europe and North America were engaged in a far-reaching unity of science movement. In this period of deep social and political divisions, scientists collaborated to try to unify sciences across disciplinary boundaries and to set up the international scientific community as a model for global political co-operation. This volume explores the unity of science movement, providing a synthetic view of its pursuits and placing it in its historical context as a scientific and political force. Through a coherent set of original case studies that look at the significance of various projects and strategies for unification, the essays demonstrate the great variety of manifestations of this ambitious pursuit. In so doing the book makes visible important historical developments, showing how scientists participated in, and actively helped to create, an interwar ideology of unification and bringing to light the cultural and political significance