The historical ratio of Catholics to Protestants in unified Germany was approximately 30% to 70%. Catholicism predominated in the western provinces of Prussia on the border with France and the Benelux, in the southern states, and in the eastern provinces of Prussia on the former Polish lands.

The creation of a unified German state led by Protestant Prussia prompted German Catholics to form their own party to more effectively defend their confessional interests. Thus, in 1870, the Catholic Centre Party was established.

The first decade of the German Empire was marked by the "Kulturkampf" – a struggle by the secular governments of the German states against the autonomous rights of the Catholic Church. Priests were banned from political propaganda, the clergy were deprived of the right to oversee schools, church appointments were handed over to state officials, civil marriage was introduced, and the Jesuit order was banned. However, all these repressive measures only united the Catholic community. By the late 1870s, Chancellor Otto von Bismarck considered that socialists posed a greater threat to the internal security of the state than Catholics and ended the "Kulturkampf." Most of the restrictive laws, except for the recognition of civil marriages and the expulsion of the Jesuits, were repealed.