Around 1200, the Counts of Calw-Vaihingen built a castle with a shield wall, keep, and moat on the hill, which had already been settled by the Celts. Count Konrad von Calw-Vaihingen called himself Count of Neuenbürg from the mid-13th century onward. The town of Neuenbürg was first mentioned in documents in the 13th century.

The Habsburg royal family also expressed interest in the strategically located castle at the time, purchasing Neuenbürg Castle for the empire. Neuenbürg itself was part of Baden at the time. However, the Württembergers would soon take over the castle from imperial property.