Map of the Roman Empire - Narbonensis

Narbonensis
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Ancient Narbonensis This province in southern France was one of the four large provinces of Gallia along with Aquitania, Lugdunensis, and Belgica. Julius Caesar made Gallia Narbonensis a senatorial province, administered by a proconsul.  Also see Gallia

Gallia Narbonensis (English: Narbonese Gaul, from the chief settlement of Narbonne) was a Roman province located in what is now Languedoc and Provence, in southern France. It was also known as Gallia Transalpina (Transalpine Gaul), which was originally a designation for that part of Gaul lying across the Alps from Italia and it contained a western region known as Septimania (see Septimania timeline). It became a Roman province in the late 2nd century BCE, constituting the first significant Roman territory outside of Italy. Its boundaries were roughly defined by the Mediterranean Sea to the south and the C�vennes and Alps and north and west.

Names
The province of Gallia Transalpina (Transalpine Gaul) was later renamed Gallia Narbonensis, after its capital the Roman colony of Narbo Martius (Narbonne), founded on the coast in 118 BCE. The Romans called it Provincia Nostra ("our province") or simply Provincia ("the province"), being the first significant permanent conquest outside the Italian peninsula. The name has survived in the modern French name of the region, Provence, now a r�gion of France.

Founding
By the mid-second century BCE, Rome was trading heavily with the Greek colony of Massalia (modern Marseille) on the southern coast of Gaul. Massalia, founded by colonists from Phocaea, was by this point centuries old and quite prosperous. Rome entered into an alliance with Massalia, by which it agreed to protect the town from local Gauls and other threats, in exchange for a small strip of land that it wanted in order to build a road from Italy to Spain, to assist in troop transport. The Massalians, for their part, cared more for their economic prosperity than they did their territorial integrity. In this strip of land, the Romans founded the town of Narbonne, which turned out to be a major trading competitor with Massalia. It was from this that what was then the province of Transalpine Gaul was founded.

Later history
Bordering directly on Italy, control of the province gave the Roman state several advantages, such as control of the land route between Italy and the Iberian peninsula; a buffer against attacks on Italy by tribes from Gaul; and control of the lucrative trade routes of the Rhone valley, over which commercial goods flowed between Gaul and the trading center of Massalia. It was from the capital of Narbonne that Julius Caesar began his Gallic Wars.

The area became a Roman province in 121 BCE, originally under the name of Gallia Transalpina (Transalpine Gaul). This name was chosen to distinguish it from Cisalpine Gaul, the part of Gaul on the near side of the Alps to Rome. At one point, Narbonese Gaul and Transalpine Gaul were governed as separate territories - when the Second Triumvirate was formed, Lepidus was given responsibility for Narbonese Gaul and Spain, while Mark Antony was given Cisalpine and Transalpine Gaul. - Wikipedia