About the middle of the third century of our era Arabia was enclosed on the north and north-east by the rival empires of Rome and Persia, to which the Syrian desert, stretching right across the peninsula, formed a natural termination. In order to protect themselves from Bedouin raiders, who poured over the frontier-provinces, and after laying hands on all the booty within reach vanished as suddenly as they came, both Powers found it necessary to plant a line of garrisons along the edge of the wilderness. Thus the tribesmen were partially held in check, but as force alone seemed an expensive and inefficient remedy it was decided, in accordance with the well-proved maxim, _divide et impera_, to enlist a number of the offending tribes in the Imperial service. Regular pay and the prospect of unlimited plunder--for in those days Rome and Persia were almost perpetually at war--were inducements that no true Bedouin could resist. They fought, however, as free allies under their own chiefs or phylarchs. In this way two Arabian dynasties sprang up--the Ghassánids in Syria and the Lakhmites at Ḥíra, west of the Euphrates--military buffer-states, always ready to collide even when they were not urged on by the suzerain powers behind them. The Arabs soon showed what they were capable of when trained and disciplined in arms. On the defeat of Valerian by the Chosroes Sábúr I, an Arab chieftain in Palmyra, named Udhayna (Odenathus), marched at the head of a strong force against the conqueror, drove him out of Syria, and pursued him up to the very walls of Madá’in, the Persian capital (265 A.D.). His brilliant exploits were duly rewarded by the Emperor Gallienus, who bestowed on him the title of Augustus. He was, in fact, the acknowledged master of the Roman legions in the East when, a year later, he was treacherously murdered. He found a worthy successor in his wife, the noble and ambitious Zenobia, who set herself the task of building up a great Oriental Empire. She fared, however, no better than did Cleopatra in a like enterprise. For a moment the issue was doubtful, but Aurelian triumphed and the proud 'Queen of the East' was led a captive before his chariot through the streets of Rome (274 A.D.). These events were not forgotten by the Arabs. It flattered their national pride to recall that once, at any rate, Roman armies had marched under the flag of an Arabian princess. But the legend, as told in their traditions, has little in common with reality. Not only are names and places freely altered--Zenobia herself being confused with her Syrian general, Zabdai--but the historical setting, though dimly visible in the background, has been distorted almost beyond recognition: what remains is one of those romantic adventures which delighted the Arabs of the _Jáhiliyya_, just as their modern descendants are never tired of listening to the _Story of ‘Antar_ or to the _Thousand Nights and a Night_. [Sidenote: Málik the Azdite.] [Sidenote: Jadhíma al-Abrash.]