Civitas Tungrorum

The Civitas Tungrorum was a large Roman administrative district dominating what is today eastern Belgium, and the southern Netherlands. In the early days of the Roman empire it was in the province of Gallia Belgica, but it later joined the neighbouring lower Rhine river border districts, within the province of Germania Inferior. Its capital was Aduatuca Tungrorum, which is modern Tongeren.

Like many Roman administrative districts, this one was named after the tribal grouping that lived there, the Tungri, although in this case the Tungri is not a name known from the area before it became part of the Roman empire.

The exact definition of the civitas probably corresponded at least roughly to the area of the large medieval Catholic diocese of Liège, which was reduced in 1559. Many early medieval dioceses were based upon older Roman provinces. And it is known that this diocese saw itself as the diocese of the Civitas Tungrorum. However, doubts exist about exact borders in this case due to the fact that the northern part of the civitas was for a long time pagan Frankish, and outside of Roman or Catholic influence. Edith Wightman, considering the question of the locations of the tribes Caesar originally met here, goes as far as saying that this region "had the least stable political situation of any within later Belgica, and since the pattern was repeated in the Middle Ages, bishopric boundaries are of no help".

In modern terms, the region covered all or most of eastern Belgium. The southern part is generally treated as if it had the same boundaries as the later diocese.

There is less certainty about the borders of the civitas to the north and east, where pagan Franks settled in between the times of Saint Servatius and Lambert of Maastricht, leading to a possible disruption of administrative districts.

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