Oea was situated between these two, on the western side of a small bay, formed by the projection of a rocky point of land into the sea. A triumphal arch dedicated to the emperors Marcus Aurelius, and Lucius Verus, and considered the finest monument of that kind remaining, with several other ancient relics, give reason to suppose that it may have been a splendid city; and it is mentioned as such by Pliny, Strabo, and some other writers of the latter days of the Roman empire. We however learn nothing from them respecting its history; and in the year 647 of the Christian æra, when the Saracens invaded Africa, Leptis and Sabrata had sunk into comparative insignificance, while Oea had appropriated to itself the name of the whole district, and was a large, wealthy and strong city. The seat of government of the Roman, or rather Greek dominions in Africa, continued to be Carthage, where resided the emperor's Prefect or lieutenant; Utica, Hippo, and other ancient places were still flourishing, and several had grown up to importance, whose names do not appear in the pages of Roman history; of these the principal were Sufetala, Bugia, and Tingi or Tangiers. The Saracens appeared before Tripoli in number forty thousand, under Abdallah, governor of Egypt, and Zobeir a distinguished soldier; but the strength of its walls baffled the attempts of enemies totally unacquainted with the art of besieging, and enabled its inhabitants to remain secure, until an immense army had been collected by the Prefect for its relief. It at length appeared, and actions daily took place, in which nothing was decided in favor of either party. Gregory the Prefect fought with gallantry, attended in the field by his daughter; yet this example was not sufficient to encourage his troops, although they far outnumbered their enemies; and as a last effort, he proclaimed that his daughter's hand with a hundred thousand pieces of gold, should be the reward for the head of the Saracen general. Thus excited, the African youths took courage, and Abdallah considering his own person as too important to be exposed to such dangers, remained during the ensuing action in his tent; but he was soon shamed from this retreat by the fiery Zobeir, who insisted upon his replying to Gregory's proclamation, by promising the lady and a similar reward for the head of the Prefect.