Arabia Petraea

Arabia Petraea, also called Provincia Arabia or simply Arabia, was a frontier province of the Roman Empire beginning in the 2nd century; it consisted of the former Nabataean kingdom in Transjordan, southern Syria, the Sinai Peninsula and northwestern Arabian peninsula. Its capital was Petra. It was bordered on the north by Syria, on the west by Iudaea (merged with Syria from 135 AD) and Aegyptus, and on the south and east by the rest of Arabia, known as Arabia Deserta and Arabia Felix.

It was annexed by Emperor Trajan, like many other eastern frontier provinces of the Roman Empire, but held onto, unlike Armenia, Mesopotamia and Assyria, well after Trajan's rule – its desert frontier being called the Limes Arabicus. It produced no usurpers and no emperors (Philippus, though Arab, was from Shahbā, a Syrian city added to the province of Arabia at a point between 193 and 225 — Philippus was born around 204). As a frontier province, it included a desert populated by the nomadic Saraceni, and bordering the Parthian hinterland.

Though subject to eventual attack and deprivation by the Parthians and Palmyrenes, it had nothing like the constant incursions faced in other areas on the Roman frontier, such as Germany and North Africa, nor the entrenched cultural presence that defined the other, more Hellenized, eastern provinces.