Already in 1091 the duke Berthold II of Zähringen ordered the construction of the Castrum de Friburch on the Schlossberg (castle hill) of Freiburg in beautiful Romanesque style. This castle was praised later by the poet Hartmann von Aue. The Duke's servants and craftsmen lived at the foot of the mountain in the area of what today is the southern part of the historic center, but it was only in 1120 when his son Konrad, with the approval of emperor Henry IV, granted the settlement market rights, thus ending the startup phase of Freiburg.