While in many parts of Germany in the 19th century Luth and Ref churches decided to form united churches, the two confessions continued to exist side by side in the former kingdom of Hanover, when Hanover became part of Prussia. In 1882 the Reformed congr were permitted by the king of Prussia to found an autonomous Evangelical-Reformed church in the Province of Hanover. Reformed congr from other provinces became part of this church: Reformed congr of East Frisia, of the Dukedoms of Bentheim and Lingen, of Plesse (in the neighborhood of Göttingen), and of Bremen; in addition, several Huguenot congr joined the church.
Much later, in 1988, the Evangelical-Reformed Church in Bavaria also united with this church. Some of the congr in Bavaria were founded by Huguenots, others go back to the time of the Reformation (under the influence of the Reformation in Zurich, several congr were founded in the Allgäu), still others came into existence through refugee settlement from the Palatinate, e.g.,the Reformed congregation in Munich. In 1920 they adopted their own constitution and existed in close collaboration with the Evangelical-Lutheran Church of Bavaria.
Today this church consists of 142 congr with over 200,000 members spread all over Germany. It is one of the smaller churches in Germany, and, in contrast to the Church of Lippe, it is not a territorial church but a federation of congr fully responsible for themselves in all matters.