It is not known exactly when the Tiefburg castle was built or by whom. It is assumed that it was built in the 12th century, possibly by the Abbey of Lorsch or the Count Palatinates of the Rhine (later known as the Prince Electors of the Palatinate), who set up residence in nearby Heidelberg around this time. It is also possible that the castle had its origins in a fortiied estate. The knights of Handschuhsheim who lived in the Tiefburg were initially unfree knights, known as ministeriales, in the service of the Abbey of Lorsch, and later on vassals of the Prince Electors of the Palatinate. The dynasty died out when the last knight of Handschuhsheim, Johannes (Hans) V., died aged 16 on 31st December 1600 from injuries sustained in a duel. Through inheritance, the Tiefburg became the property of the barons of Helmstatt (who became counts of Helmstatt in the 18th century).
Tiefburg was badly damaged in the Thirty Years‘ War. In 1689 it fell victim to the War of the Palatine Succession and became uninhabitable, whereupon the Helmstatts built a new residence in the immediate vicinity. The original gate of this new residence can still be seen to the east of the square in front of the Tiefburg. Count Raban von Helmstatt had the Tiefburg restored in the years 1910 to 1913.
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.