as probable that the tide of conquest would have flowed eastward in A.D. 641 or 642, even had he attempted nothing.  What alone we can be sure of his, that no acquiescence on his part, no abstention from warlike enterprise, no submission short of the acceptance of Islamism, would have availed to save his country for more than a very brief space from the tramp of the hordes that were bent on enriching themselves with the plunder of the whole civilized world, and imposing on all the nations of the earth their dominion and their religion.

From the citadel of Rei, Isdigerd, in A.D. 641, sounded the call to battle with no uncertain note.  His envoys spread themselves through Media, Azerbijan, Khorassan, Gurgan, Tabaristan, Merv, Bactria, Seistan, Kerman, and Farsistan (or Persia Proper), demanding contingents of troops, and appointing, as the place of rendezvous, the small town of Nehavend, which is in the mountain region, about fifty miles south of Hamadan.  The call was responded to with zeal; and in a short time there was gathered together at the place named an army of 150,000 men.  Firuzan, one of the nobles who had commanded at Kadisiyeh, was made general-in-chief.  The design was entertained of descending on Holwan, and thence upon the lowland region, of re-taking Ctesiphon, crossing the great rivers, and destroying the rising cities of Kufa and Busrah.  But the Arabs were upon the alert, and anticipated the intended invasion.  Noman, son of Mokarrin, who commanded at Ahwaz, was hastily commissioned by Omar to collect the Arab troops stationed in Irak, Khuzistan, and the Sawad, to put himself at their head, and to prevent the outbreak by marching at once on Nehavend.  He succeeded in uniting under his standard about 30,000 soldiers, and with this moderate force entered the mountain tract, passed Holwan and Merj, and encamped at Tur, where he expected the attack of the enemy.  But Firuzan had now resolved to maintain the defensive.  He had entrenched himself strongly in front of Nehavend and was bent on wearing out the patience of the Arabs by a prolonged resistance.  Noman, finding himself unmolested, advanced from Tur to the immediate neighborhood of Nehavend, and endeavored to provoke his adversary to give battle, but without effect.  For two months the two hosts faced each other without fighting.  At last, the stores of the Arabs, as well as their patience, began to fail; and it was necessary to employ some device, or to give up the war altogether.  Hereupon, Noman, by the advice of two of his captains, had recourse to a stratagem.  He spread a report that Omar was dead, and breaking up from from his camp began a hasty retreat.  The plan succeeded.  Firuzan quitted his entrenchments, and led his army on the traces of the flying foe.  It was two days before he reached them, and on the third day the battle began.  Noman, having addressed his soldiers and made arrangements concerning the command in case of his own death, mounted a milk-white steed, and gave the signal for the fight