When the Roman envoys approached the presence of the chagan, they were commanded to wait at the door of his tent till, at the end perhaps of ten or twelve days, he condescended to admit them. If the substance or the style of their message was offensive to his ear, he insulted, with real or affected fury, their own dignity and that of their prince; their baggage was plundered, and their lives were only saved by the promise of a richer present and a more respectful address. But his sacred ambassadors enjoyed and abused an unbounded license in the midst of Constantinople; they urged, with importunate clamours, the increase of tribute or the restitution of captives and deserters; and the majesty of the empire was almost equally degraded by a base compliance, or by the false and fearful excuses with which they eluded such insolent demands. In the language of a barbarian without guile, the prince of the Avars affected to complain of the insincerity of the Greeks; yet he was not inferior to the most civilised nations in the refinements of dissimulation and perfidy. As the successor of the Lombards, the chagan asserted his claim to the important city of Sirmium, the ancient bulwark of the Illyrian provinces. The plains of lower Hungary were covered with the Avar horse, and a fleet of large boats was built in the Hercynian wood, to descend the Danube and to transport into the Savus the materials of a bridge. But as the strong garrison of Singidunum, which commanded the conflux of the two rivers, might have stopped their passage and baffled his designs, he dispelled their apprehensions by a solemn oath that his views were not hostile to the empire. He swore by his sword, the symbol of the god of war, that he did not, as the enemy of Rome, construct a bridge upon the Savus. “If I violate my oath,” pursued the intrepid Baian, “may I myself, and the last of my nation, perish by the sword; may the heavens and fire, the deity of the heavens, fall upon our heads! may the forests and mountains bury us in their ruins! and the Savus returning, against the laws of nature, to his source, overwhelm us in his angry waters!” After this barbarous imprecation, he calmly inquired what oath was most sacred and venerable among the Christians, what guilt of perjury it was most dangerous to incur. The bishop of Singidunum presented the Gospel, which the chagan received with devout reverence. “I swear,” said he, “by the God who has spoken in this holy book, that I have neither falsehood on my tongue nor treachery in my heart.” As soon as he rose from his knees, he accelerated the labour of the bridge, and despatched an envoy to proclaim what he no longer wished to conceal. “Inform the emperor,” said the perfidious Baian, “that Sirmium is invested on every side. Advise his prudence to withdraw the citizens and their effects, and to resign a city which it is now impossible to relieve or defend.”