This chapter sheds light on the historical background of industrialization and the accompanying social upheavals at the end of the 19th century in the USA and Germany, which confronted Walter Rauschenbusch and Martin Rade. It provides an economic-historical and socio-political classification as well as a contextualization in the history of theology and social ethics. In addition, American and German Social Protestantism are directly compared. The chapter then presents biographical sketches of Rauschenbusch and Rade as well as descriptions of their works: for Rauschenbusch, these are his four most important publications; for Rade, the focus is primarily on his involvement with the Evangelical Social Congress and his editorship of the “Christliche Welt,” but also his attitude toward Karl Barth and dialectical theology. Finally, both protagonists are directly compared, particularly with regard to their attitudes toward the Kingdom of God theology and the socio-political question.