From Stadtwiki Baden-Baden
The Stiftskirche (collegiate church) belongs to the oldest buildings of Baden-Baden's historic center and is an important part of its cityscape. Its present late gothic appearance is the result of numerous building phases during different centuries. Containing the tombs of the margraves of Baden and as a collegiate church it became particularly important.
Already a deed of gift of Emperor Otto III from 987 proves the existence of a church in medieval Baden-Baden, that could have been situated at the Stiftskirche's location today. By 1200 margrave Hermann V von Baden had a three-naved roman church build on the Florentinerberg. With the establishment of a collegiate in 1453 the church became a collegiate church. Therefore and because it contained the tombs of the margraves of Baden the church was expanded in the gothic style from 1452 to 1477. In the course of the Nine Years War, the church burned down almost completly in the Great Fire of 1689. During the reconstruction new baroque elements were added to the architecture. Part of these elements that still exist are the bulbous domes of the years 1712 and 1713. In 1808 the secularization led to the dissolution of the collegiate. In the years 1861 to 1867 the baroque elements were taken back as much as possible, in order to turn the church into a gothic church again. A thermal heating system was added to the building. The thermal water of the Florentinerberg flowed through a system of copper pipes. The moisture caused by this system was very harmful for the masonry. A lot of renovations became necessary. The thermal heating was used until 1954.
- Helmuth Bischoff Baden-Baden: Die romantische Bäderstadt im Tal der Oos. Kurbetrieb zwischen Casino, Park und Kloster. DuMont, Köln 1996, ISBN 3-7701-3086-3.
- Bäuerle und andere Stadtführer Baden-Baden - Altstadt - Villen - Allee Arbeitskreis für Stadtgeschichte Baden-Baden e.V. 1994, ISSN-NR. 0936-742X