With the end of the sovereign church regime in 1918, the Protestant churches in Germany were faced with revolutionary challenges. New legal and organizational structures had to be created and a relationship with the young democracy had to be developed. In this context, the problems of the regional churches, which had now become independent, were quite different. In addition, the idea of a union of the individual churches was revived, which became concrete in the founding of the German Evangelical Church Confederation in 1922. The present volume is dealing with the institutional changes on the basis of concrete territorial-historical studies. In addition to exemplarily selected regional churches of southern, western and central Germany, a special focus is laid on the changes for the German congregations abroad in the Baltic States, Poland and Romania.