The Roman Republic had been aggressively expanding in the southern Italian mainland for a century before the First Punic War. It had conquered peninsular Italy south of the River Arno by 272 BC, when the Greek cities of southern Italy (Magna Graecia) submitted at the conclusion of the Pyrrhic War. During this period Carthage, with its capital in what is now Tunisia, had come to dominate southern Spain, much of the coastal regions of North Africa, the Balearic Islands, Corsica, Sardinia, and the western half of Sicily, in a military and commercial empire. Beginning in 480 BC, Carthage had fought a series of inconclusive wars against the Greek city states of Sicily, led by Syracuse. By 264 BC Carthage and Rome were the preeminent powers in the western Mediterranean. The two states had several times asserted their mutual friendship via formal alliances: in 509 BC, 348 BC and around 279 BC. Relationships were good, with strong commercial links. During the Pyrrhic War of 280–275 BC, against a king of Epirus who alternately fought Rome in Italy and Carthage on Sicily, Carthage provided materiel to the Romans and on at least one occasion used its navy to ferry a Roman force.