When the Reformation preachers appeared at the beginning of 1523, the leaders of the city and its citizenry struggled to find a religious common ground for the free Imperial City. After the defeat in the Peasants’ War in May 1525 Mühlhausen came under the auspices of the neighbouring lords, which exerted considerable influence over the city’s church policies. Since the lords held different views towards the Reformation, Mühlhausen had to change its denomination several times. For a long time, the city council held on to Catholicism, hoping that this was the best path to have the Emperor restore its unqualified status as a free Imperial City. Only after the city was able to cast off the patronage by its neighbouring princes and counts in 1548, more council members became followers of the Reformation. In 1566, the interim period, in which Catholicism and Protestantism coexisted within the city, came to an end. As the Kornmarkt church was closed and Catholic priests were gradually displaced, the parish structure of the remaining Catholics disappeared. From that time onward Mühlhausen pursued uncompromising Protestant policies, which only ended in 1802 when the kingdom of Prussia annexed the city. The Catholic share of Mühlhausen’s population still continued to grow due to the influx of Catholics from the Eichsfeld and the Prussian military presence in the 19th century. However, an officially recognised Catholic parish was not established until 1849. Since all attempts to use one of the numerous vacant medieval churches failed, the St. Boniface Chapel was built in 1851 at the Blobach Square. The half-timbered building was enlarged several times but was eventually too small for a community that had continued to grow throughout the industrial period. In 1907, St. Joseph’s Church near the railway station was consecrated, replacing St. Boniface Chapel as the centre of Mühlhausen’s Catholic community. The old building at the Blobach Square, which was extensively refurbished in 2008/09, is still used for church services. The tower annexe from 1862 today serves as access to a Catholic kindergarten that was opened in 1930 in the newly constructed welfare house south of the chapel.