Most of the Bedouin tribes in Mesopotamia embraced Islam. There were exceptions, and the story of the Beni Iyâdh is singular. They migrated to the north and found an asylum in Roman territory. But Omar, nettled at their disappearance, and fearing lest they should remain a thorn in his side, demanded their extradition from the Byzantine Court, on pain of the expulsion of all the Christian tribes living under his protection. And the Emperor, unwilling to expose these to ill-treatment, complied with the demand.[340] Equally remarkable is the tale of the Beni Taghlib. [Sidenote: Beni Taghlib allowed to pay tithe.]They tendered their submission to Welîd ibn Ocba, who, solicitous for the adhesion to Islam of this great and famous race, pressed them with some rigour to abjure their ancient faith. Omar was much displeased at this,--‘Leave them,’ he wrote, ‘in the profession of the Gospel. It is only within the bounds of the Peninsula, where are the Holy Places, that no polytheist tribe is permitted to remain.’ Welîd was removed from his command; and it was enjoined on his successor to stipulate only that the usual tribute should be paid, that no member of the tribe should be hindered from embracing Islam, and that the children should not be educated in the Christian faith. The tribe, deeming in its pride the payment of ‘tribute’ (_jazia_) an indignity, sent a deputation to the Caliph:--They were willing, they said, to pay the tax if only it were levied under the same name as that taken from the Moslems. Omar evinced his liberality by allowing the concession; and so the Beni Taghlib enjoyed the singular privilege of being assessed as Christians at a ‘double _Tithe_,’ instead of paying _Jazia_, the obnoxious badge of subjugation.[341] [Sidenote: Fall of Cæsarea. A.H. XVII. A.D. 638.] The last place to hold out in Syria was Cæsarea. It fell a last in the fifth year of Omar’s Caliphate. Amru had sat long before it. But, being open to the sea, and the battlements landward strong and well manned, it resisted all his efforts; and although Yezîd sent his brother Muâvia with reinforcements from Damascus, the siege was prolonged for several years. Sallies persistently made by the garrison, were driven back with equal constancy. In the end, as we are told, by the treachery of a Jew, a weak point was discovered in the defences. The city was carried by storm, with prodigious carnage of the wretched inhabitants. Four thousand prisoners, of either sex, were despatched as part of the prey to Medîna, and there distributed in slavery.[342] [Sidenote: Khâlid brought to trial. A.H. XVII. A.D. 638–9.]