Oberkirche, Bad Frankenhausen

The church was completed on 25 April 1382 as a basilica in the Gothic style. The fraternity Corporis Christi ("Body of Christ") had it built on the foundations of a dilapidated Romanesque structure. For a long time, the Oberkirche dominated the image of Frankenhausen more than the other churches in the town. The oldest part of the nave was constructed as a vaulted building and a nave with several aisles. Pointed-arched Gothic windows and doors adorned the building. The tower originally had a pointed roof with four small side towers. In its heyday, the Oberkirche had many altars and enjoyed a high income.

In the course of the German Peasants' War whose battle near Frankenhausen raged above the town on 15 May 1525, the Oberkirche was damaged and looted. The counts of Schwarzburg were basically sympathetic to Martin Luther's work but tried to prevent the implementation of the Reformation in their territories. That is why their subjects in this region did not gain their religious freedom until 1539. In the same year, the last Catholic service was held in the Oberkirche. Afterwards, the first Protestant clergyman was appointed to the church.

During the Thirty Years' War (1618–1648), the Oberkirche was again plundered from 21 to 24 October 1632. As early as 1692, dilapidation was documented. Lack of funds was the cause of a very sluggish renovation. The view from the south side in particular still bears witness today to the changes that were carried out at random. In 1724, the first funeral sermon could be held in the renovated church, which was consecrated again on 14 September 1727.

During the Seven Years' War (1756–1763), passing troops plundered the church once again. On 27 May 1759, the top of the Oberkirche tower fell victim to one of the many town fires. A spread to the entire church building was prevented, but overzealous people caused great damage when they tore out the pipes of the organ to save them from the flames. As early as 13 July 1760, work began on rebuilding the upper part of the tower, which was completed as a Baroque structure on 22 August 1761. In the process, the already existing leaning of the tower was counteracted structurally. The bells destroyed in the fire were replaced in 1765.

During the French campaign of conquest, the church suffered new damage in 1806 when 2.678 captured Prussians were brought to Frankenhausen under the guard of 300 Frenchmen and both of the town's churches (Oberkirche and Unterkirche, Upper and Lower Church) were used as prison camps. The interior of the Oberkirche was subsequently in need of renovation and the organ unusable. A new organ and the necessary renovation work were financed by donations and the new organ was consecrated on 1 May 1867.