Ara Ubiorum

ARA UBIO´RUM an altar and sacred place in the territory of the Ubii, on the west side of the Rhine. The priest of the place was a German. (Tac. Ann. 1.57.) This altar is first mentioned in the time of Tiberius. In A.D. 14, Germanicus was at the Ara Ubiorum, then the winter-quarters of the first and twentieth legions, and of some Veterani. (Tac. Ann. 1.39.) In the time of Vespasian (Tac. Hist. 4.19, 25), Bonna (Bonn), on the Rhine, is spoken of as the winter-quarters of the first legion. As the winter-quarters seem to have been permanent stations, it is possible that the Ara Ubiorum and Bonna maybe the same place. The Ara Ubiorum is placed, by Tacitus, sixty miles (sexagesimum apud lapidem, Ann. 1.45), from Vetera, the quarters of the fifth and twenty-first legions; and Vetera is fixed by D'Anville at Xanten, near the Rhine, in the former duchy of Cleves. This distance measured along the road by the Rhine brings us about Bonn. The distance from Vetera to Cologne, which some writers would make the site of the Ara Ubiorum, is only about 42 Gallic leagues, the measure which D'Anville assumes that we must adopt. If we go a few miles north of Bonn, to a small eminence named Godesberg, which may mean God's Hill, or Mons Sacer, we find that the distance from Vetera is 57 Gallic leagues, and this will suit very well the 60 of Tacitus, who may have used round numbers. If we compare the passages of Tacitus (Tac. Ann. 1.37, 39), it appears that he means the same place by the Civitas Ubiorum,and the Ara Ubiorum.By combining these passages with one in the Histories (Agrippinenses, 4.28), some have concluded that the Ara Ubioram is Cologne. But Cologne was not a Roman foundation, at least under the name of Colonia Agrippinensis, until the time of Caudius, A.. 51; and the identity, or proximity, of the Civitas Ubiorum, and of the Ara Ubiorum, in the time of Tiberius, seems to be established by the expressions in the Annals (1.37, 39); and the Ara Ubiorum is near Bonn.
[G.L]