ABSTRACT
MUCH more interesting than the harlequin patchwork of Transpadane Gaul are the regions further east. Histria and Venetia may well be taken together, not only for our present purpose, but also as constituting, together with the territory of the Cenomani (who lived in the stretch of territory between the Adige and the Adda) the tenth Augustan regio of Italy-previously considered (except Histria) as part of Cisalpine Gaul. The peninsula of Histria, and therefore also the tenth regio was bounded on the east by the river Arsia (now the Arsa), which to Pliny was accordingly the limit of " Italia," a little west of the modern frontier of Italy at Fiume; the dividing-line between it and Venetia was the river Formio, so that Tergeste (modern Trieste), which seems to be an Illyrian name 1 meaning "market," belonged not to the Histri, but to the Carni in Venetia. We saw above (p. 146) that the western boundary is somewhat indefinite; here we adhere to the eastern boundary then accepted for the Transpadana. On the north-west the frontier ran along the range of hills separating the valleys of the Adda and the Oglio and then up to the summit of the Rretic Alps and so, following the ridge of the Venetic, Carnic, and Julian Alps to the Karst plateau back to the head-waters of the Arsa. But this includes also the southern tribes of the Rreti, whom we shall discuss here. For the boundaries of the Rreti were by no means identical with those of the two later Roman provinces called Rretia (that is Rretia proper to the south, and Vindelicia to the north, the latter all but entirely Keltic and outside our field), any more than the boundaries of the Veneti were
16~ identical with those of the regio Venetia. On the south the boundary of Venetia was the river Po itself, which here was broad enough to form for long an effective barrier to invaders.
