The landgrave town of Weißensee lies in the heart of Thuringia in the Erfurt Basin. The small town has always been of particular importance, as it was geographically located at the crossroads of the salt or copper road running from Nuremberg via Erfurt to Magdeburg and the connection between Eisenach and the Neuenburg in Freyburg an der Unstrut, which was important for the Ludovingian territory.

The town of Weißensee was founded around the year 1200 as a planned new town by the Ludovingian landgraves of Thuringia and is one of the most important town foundations in Thuringia in the 12th and 13th centuries. The starting point for the development of the town was the enormous castle complex of the landgraves, which was soon to become a center of Ludovingian power. Along with the castle, a first settlement with the parish church of St. Nikolai grew up on the eastern shore of the Weißer See.

The actual town was founded with the town hall and the town church of St. Peter & Paul to the east of the castle. Mentioned in documents as early as 1174 as "wyssense", Weißensee received its town charter on March 14, 1265.