Around 1007, Emperor Henry II moved St. George's Abbey from its former location on the Hohentwiel in Singen to Stein am Rhein — at that time, little more than a small fishing village on the Rhine. The move was a means to strengthen his presence at this strategic point, where major roads and river routes intersected. He gave the abbots extensive rights over Stein and its trade so that they could develop it commercially. In this, they were very successful and Stein am Rhein rapidly became a flourishing and prosperous town which, in the 15th century, was itself (if briefly) granted reichsfrei status.
The abbey also prospered and, in the 15th century, completely rebuilt its premises, which remain a significant example of late Gothic architecture in the region. The last and greatest abbot, David von Winkelsheim, who came to power in 1499, completed the building works and added a spectacular suite of Renaissance frescoes that are among the earliest known in northern Europe.
Under the Reformation however, the abbey was secularised and its assets taken over by Zürich. Abbot von Winkelsheim negotiated a settlement with the Zürich authorities, whereby, although control of the abbey was handed over to them, he and the remaining monks would be allowed to remain on the premises until their deaths. Zürich however, suspected the abbot of collusion with the Habsburgs and locked him up in his new rooms. He was able to escape to Radolfzell, but died shortly after, in 1526.
The Gottfried Keller Foundation aims the acquisition of major works from Switzerland and abroad, to entrust them as loans to Swiss museums or to return them to their original locations. Among other, the foundation acquired the St. Georgen Abbey. The collection comprises more than 8,500 paintings, sculptures and other art objects in around 110 museums respectively locations in Switzerland.
The buildings remained unharmed until the 19th century, when they were used by their owners for a number of industrial purposes, during which they suffered considerable damage. A Protestant pastor acquired them, and left them in trust for the community, thus saving them. Since 1945, they have accommodated a museum.
The banqueting hall, or Festsaal, containing the frescoes commissioned by David von Winkelsheim, and the cloisters are of especial interest in a building complex.
The abbey church, which dates predominantly from the 12th century, has also survived intact, and is now a Protestant parish church.
References:Sigmaringen Castle was first mentioned in the year 1077 in the chronicles of Petershausen monastery. The oldest parts of the castle are concealed beneath the alterations made during the 17th and the 19th centuries. The secret of the earliest settlement built on this defendable rock will never be fully revealed: large-scale excavation work would be necessary, which the extensive land development renders impossible. Judging from the many Roman remains unearthed in the area around Sigmaringen, the 12th century keep known as the 'Roman Tower' could be traced back to a Roman predecessor.
The castle remains that have been preserved (gate, great hall and keep) date back to the Staufer period around 1200. The castle remains were integrated into subsequent buildings. The foundations of the castle buildings are to a large extent identical to the surrounding castle wall.
These remains give us a good idea of how the castle might have looked during the 12th century.