Venetia et Histria

Venetia et Histria (Latin: "Regio X Venetia et Histria") was an administrative subdivision in the northeast of Roman Italy. It was originally created by Augustus as the tenth "regio" in 7 AD alongside the nine other "regiones". The region had been one of the last regions of Italy to be incorporated into the Roman Empire. It was later renamed by Diocletian the "VIII provincia Venetia et Histria" in the third century. Its capital was at Aquileia, and it stretched geographically from the Arsia River in the east in what is now Croatia to the Abdua in the current Italian region of Lombardy and from the Alps to the Adriatic Sea.
Etymology.
The name "Venetia et Histria" was used for the region was in part because of the "early and unwavering" loyalty of the local Veneti people to the Roman state. This name was also preferred to using the name of a more rebellious group like the Celtic Cenomani because of the Roman belief in a shared descent with the Veneti from the Trojans.
History.
Pliny the Elder was the only Roman writer to discuss the Augustan subdivision of Italy into "regiones" directly and did so in his "Natural History". The region's new borders did not cleave directly to pre-existing regional identities. Verona which had traditionally been seen as part of Transpadana as it was north of the Po was not incorporated into the region with that name, "regio XI" but was made part of "regio X".
Neratius Pansa, a Roman senator of the late first century AD, is believed, on the basis of epigraphic evidence, to have led a census here under the reign of the Emperor Vespasian in 73-74.
Geography.
In the late first century AD, Pliny identified 36 cities in the region, while Strabo identified 12 in the same area. The CIL has identified 16 separate settlements using epigraphic evidence, and other historians have argued that "the density of cities for the region is not high compared to the rest of Italy".
While the capital of the region, Aquileia, was a major centre for commerce, transport, and public life in northeastern Italy, with an amphitheater that could hold more than 27,000 and a position at the centre of a wide network of roads, other cities like Concordia, Tergeste, and Altinum were also substantial regional hubs.