After in early November 1918 the grand duke, the dukes and princes of the eight monarchies, later merging into the new State of Thuringia, had abdicated and thus released each of the eight territorial Lutheran church bodies from their respective supreme governorate (summepiscopacy), Lutheran church leaders, among them the Saxe-Altenburgian court preacher Wilhelm Reichardt as one of the driving forces, decided the unification of the church bodies on 15 November 1918.
Within seven of these Lutheran church bodies majorities formed to merge, to wit: Only the Evangelical Lutheran Church of the Principality of Reuss Elder Line (Evangelisch-lutherische Kirche des Fürstentums Reuß ältere Linie) refused the merger and renamed as the Evangelical Lutheran Church in Reuss Elder Line (German: Evangelisch-lutherische Kirche in Reuß ältere Linie).
The parishioners within the Thuringia church body voted by a majority for candidates of the Nazi-submissive German Christians in the presbyteries and the synod in the unconstitutional reelection imposed by Hitler on 23 July 1933.
Nazi opponents then formed the Confessing Church of Thuringia, gradually pressed into hiding.
In 1933 Reichardt adopted the title of a state bishop (Landesbischof) and deprived the synod of its legislative rights.
In May 1945 Moritz Mitzenheim succeeded Rönck again using the constitutional title state supreme pastor.