Burtscheid abbey was founded in 997 under Emperor Otto III. The first abbot, Gregor, who came to Burtscheid from Calabria, is sometimes said to have been the brother of Theophanu, Byzantine mother of the Emperor. He was buried beneath the altar after his death in 999, and his date of death, 4 November, was kept as a feast day until the dissolution of the abbey.
In 1018 the Emperor Henry II endowed it with the surrounding territory. Also at about this time the monastery was raised to the status of an abbey, and the dedication was changed from Saints Nicholas and Apollinaris to Saints John the Baptist and Nicholas.
In 1138, the abbey was made reichsfrei by Conrad III, being granted Imperial immediacy, the privilege of being subject only to the Holy Roman Emperor, rather than to an intermediate lord. The abbey was under the Vogtei (loosely 'protectorship') of the Barony of Mérode until the abbey purchased its Vogtei from them, in 1649.
In 1220, under Emperor Frederick II and his chancellor, Archbishop Engelbert of Cologne, the Benedictines were evicted and replaced by Cistercian nuns who had previously been living at the Salvatorberg in Aachen, to whom the abbey's possessions were transferred. At the same time the abbey's reichsfreiheit was confirmed.
The abbey church was rebuilt in the mid-14th century, and again between 1735 and 1754 by the architect J.J. Couven.
In 1779, despite the refusal of permission by the council of Aachen, who by that time were responsible for local government in Burtscheid, the then abbess introduced a gambling house, and the street is still known today as Krugenofen Kasinostrasse.
Burtscheid was occupied by French troops in December 1792, and from September 1794 until 1804. They used the abbey church for the manufacture of balloons. In August 1802 the nunnery was secularised and dissolved.
The remaining abbey buildings are now used by a school and for residential and administrative purposes.References:
The Petersberg Citadel is one of the largest extant early-modern citadels in Europe and covers the whole north-western part of the Erfurt city centre. It was built after 1665 on Petersberg hill and was in military use until 1963. It dates from a time when Erfurt was ruled by the Electors of Mainz and is a unique example of the European style of fortress construction. Beneath the citadel is an underground maze of passageways that can be visited on guided tours organised by Erfurt Tourist Office.
The citadel was originally built on the site of a medieval Benedictine Monastery and the earliest parts of the complex date from the 12th century. Erfurt has also been ruled by Sweden, Prussia, Napoleon, the German Empire, the Nazis, and post-World War II Soviet occupying forces, and it was part of the German Democratic Republic (East Germany). All of these regimes used Petersberg Citadel and had an influence on its development. The baroque fortress was in military use until 1963. Since German reunification in 1990, the citadel has undergone significant restoration and it is now open to the public as a historic site.