Page:Bury J B The Cambridge Medieval History Vol 2 1913.djvu/323

623-626] before March was out. As to the precise route which he followed on his march to the Sarus there is considerable dispute, but there is no doubt that after a hotly contested engagement on that river Heraclius forced the Persian general to beat a hasty retreat under cover of night. It seems probable that the Emperor remained for a considerable time in this district, but our sources fail us here, and we know only that he ultimately marched to Sebastia, and crossing the Halys spent the winter in that Pontic district where he had left his army at the end of the first campaign.

The following year (626) is memorable for the great siege of the capital by the united hordes of Avars, Bulgars, Slavs, and Gepids, acting in concert with a Persian force, which endeavoured to co-operate with them from the Asiatic side of the strait. Sarbar's ill success on the Sarus led Chosroes, we are told, to withdraw from his command 50,000 men and to place them, together with a new army raised indiscriminately from foreigners, citizens, and slaves, under the leadership of Sahîn. Sahrbarâz, with the remainder of his army, took up his position at Chalcedon with orders to support the Khagan in his attack on Constantinople. Heraclius in turn divided his forces: part were sent to garrison the capital, part he entrusted to his brother Theodore who was to meet the "Golden Lances" of Sahîn, and the rest the Emperor himself retained. Of Theodore's campaign we know nothing save the result: with the assistance of a timely hail-storm and by the aid of the Virgin he so signally defeated Sahîn that the latter died of mortification. Of the operations in Europe we are better informed. From the moment that Heraclius had left the capital on his crusade against Persia the Khagan had been making vast preparations, in the hope of capturing Constantinople. It was the menace from the Danubian provinces which had recalled Heraclius in the winter of 623, and now at last the Avar host was ready. On Sunday, 29 June, on the festival of St Peter and St Paul, the advance guard, 30,000 strong, reached the suburb of Melanthias and announced that their leader had passed within the circuit of the Long Walls. Early in the year, it seems, Bonus and Sergius had sent the patrician Athanasius as an ambassador to the Avar chief, virtually offering to buy him off at his own terms. But since the spring the walls had been strengthened, reinforcements had arrived from Heraclius, and his stirring letters had awakened in the citizens a new spirit of confidence and enthusiasm. Athanasius, who had been kept a prisoner by the Khagan, was now sent from Hadrianople to learn the price at which the capital was prepared to purchase safety. He was amazed at the change in public feeling, but volunteered to carry back the city's proud reply. On 29 July 626 the Avars and the countless forces of their subject tribesmen encamped