A stone ship in the saxon westphalia. Oldenburg around 1150

With the help of the Heidenwall, Oldenburg's “name problem” can also be solved: The place name Oldenburg first appears in a document from 1108 as “Aldenburg” (old castle) - around half a century before the former count's castle in the city center was completed, as has been proven on the basis of older archaeological findings. As the castle could hardly have been considered “old” while it was still being built, its name will refer to an older castle, which, however, could not be found either on the site of today's castle or - as an alleged Germanic refuge castle - on the Geest slope of today's city center.

The Heidenwall, on the other hand, is the only verifiable castle complex in the immediate vicinity and is therefore a possible predecessor of the Grafenburg. In this context, the possible connections with the settlement in Oldenburg's city center remain unclear for the time being. The traces of settlement there - on the market square and to the east and south of it - date back to at least the 8th century, perhaps even to the 7th century AD.