COSSIO or COSSIUM(Κόσσιον), a town of the Vasates, a people in Gallia on the Garumna, above Burdigala ( Bordeaux). The Vasates of Ptolemy (Ptol. 2.7), and the Vocates of Caesar ( B. G. 3.27), an Aquitanian people, seem to be the same. They are also perhaps the Basabocates of Pliny (Plin. Nat. 4.19), unless the name indicates two conterminous peoples. The latter part of Pliny's name is clearly Vocates, and the former part (Basa) happens to be the modern name of Cossio, which is Bazas, in the department of Gironde. The diocese of Bazasprobably corresponds to the territory of the Vasates. Walckenaer ( Géogr. &c., vol. 1. p. 302) conjectures, that as the Garonne cuts this diocese into two parts, the southern part was the country of the Vasates, and the northern part between the Garonne and the Dordognewas the country of the Vocates.
In the Antonine Itin., Cossio, named Civitas Vasatas,is on the road from Bordeauxto Narbonne, and 37 1/2 M. P. from Bordeaux. The name Vasates occurs in Ausonius (Id. 2.4), who says that his family was from this place, though settled at Burdigala. In another passage (Parent.24.8), he speaks of Cossio Vasatum.Ammianus Marcellinus (Ammian. 15.11) has the name Vasatae. Bazasis in a dry sandy country. There is a description of the place by Sidonius Apoll. (Lib. viii. Ep.12).
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