Dispargum
Dispargum could refer to either the city of Duisburg on the Rhine, or the village of Duisburg near Brussels, or the city of Diest.
Disputed location
Gregory of Tours reported that the Frankish king "Chlogio" attacked from a fort named "Dispargum" on the edge of the "Thoringian" land, which is described as being west of the Rhine. One translation of what Gregory wrote, adding some Latin key words in square brackets, is as follows:This description of locations does not match the normal medieval and modern "Thuringia", which is far inland and east of the Rhine and distant from all known Frankish areas.
Dispargum has therefore been interpreted many ways, for example possibly as Duisburg on the Rhine itself, or Duisburg near Brussels, or Diest, which is also in Belgium. The latter two proposals would fit the geography well, because they are within striking distance of the Silva Carbonaria, west of the Rhine, and close to Toxandria, which is known to have been settled by the Salians in the time of Julian the Apostate. It suggests that "Thoringorum" was actually referring to the "Civitas Tungrorum". This matches Gregory's previous mention in the same passage of how the Franks had earlier settled on the banks of the Rhine and then moved into "Thoringia" on the left side of the Rhine.