While the city of Hîra was left in the immediate hands of its chief men, summary rule was set up over the adjacent country. The _Dihcâns_--great landholders and imperial tax-gatherers--had been waiting upon fortune. Seeing now that, while the Court was inactive, Khâlid carried everything before him, many began to tender submission and enter into engagements with the conqueror for payment of the revenue. Abu Bekr had, in his wisdom, strenuously enjoined that the Fellaheen, or occupiers of the soil, should be maintained in possession, and their rights scrupulously respected. The Persian demand remained unchanged on these, with the addition only of a light poll-tax. In other respects, terms were granted corresponding with those given to Hîra. Holding their ancestral faith, the people became _Zimmies_, or protected dependents. Khâlid undertook to defend them, and they on their part pledged allegiance and bound themselves to give notice if danger threatened.[127] Garrisons were quartered in a few commanding places and the troops were organised into five moveable columns. By these the country was kept in check. In this manner Khâlid held all to the south of the Euphrates, and also the lower delta, stretching from Hîra eastward across the Great River to the banks of the lower Tigris. Throughout this region none were secure from rapine but such as had entered into engagements. Fifty days’ grace was allowed to bring in the revenue, and, till it was paid, hostages were kept; a formal discharge was given on payment.[128] The tribute, as well as the booty, was distributed among the army ‘for the strengthening of the same.’ [Sidenote: Persia paralysed by internal trouble.] Persia was meanwhile hopelessly distracted. The massacre by Siroes and his jealous successors, of the male progeny near the throne, had been so ruthless and complete that no heir of the royal blood could anywhere be found, and a rapid succession of feeble claimants was set up by the princesses left to form the court. Thus paralysed, the Persians could do little more than protect the capital by holding in force the Nahr Shîr, an intervening stream that flowed down the peninsula.[129] This line was threatened by Mothanna; but Abu Bekr gave stringent orders that no advance should be made upon Medâin till all was secure behind. [Sidenote: A.H. XII. A.D. 633.] No tidings, moreover, had as yet been received from Iyâdh at Dûma, with whom (as before explained)[130] co-operation was imperative. Khâlid fretted at remaining thus inactive, ‘playing,’ as he called it, ‘for so many months the woman’s part.’ But he curbed his ardour, and contented himself with inditing two letters, in an imperious tone, one to ‘the Princes of Persia,’ the other to ‘the Satraps and the people.’ Towards the north and west, however, he employed his time more actively. [Sidenote: Khâlid takes Anbâr. Autumn, A.D. 633;]