with the Empire's subsidies. Targitius was sent in 580 to receive the tribute, but immediately after the envoy's departure Baian started with his rude flotilla down the Danube and, marching over the neck of country between that river and the Save, appeared before Sirmium and there began to construct a bridge. When the Roman general in the neighbouring fortress of Singidunum protested at this violation of the peace the Khagan claimed that his sole aim was to cross the Save in order to march through the territory of the Empire, recross the Danube with the help of the Roman fleet, and thus attack the common enemy, the Slav invaders, who had refused to render to the Avars their annual tribute. Sirmium was without stores of provisions and had no effective garrison. Tiberius had relied upon the continuance of the peace and all his available troops were in Armenia and Mesopotamia. When Baian's ambassador arrived in the capital, the Emperor could only temporise: he himself was preparing an expedition against the Slavs, but for the present he would suggest that the moment was ill-chosen for a campaign, singe the Turks were occupying the Chersonese (Bosporos had fallen into their hands in 576) and might shortly advance westward. The Avar envoy was not slow to appreciate the true position, but on the return journey he and the attendant Romans were slain by a band of Slav pillagers — this fact casually mentioned gives us some idea of the condition at this time of the open country-side in the Danubian provinces. Meanwhile Baian had been pressing forward the building of the bridge over the Save, and Solachos, the new Avar ambassador, now threw off the mask and demanded the evacuation of Sirmium. "I would sooner give your master," Tiberius replied, "one of my two daughters to wife than I would of my own free will surrender Sirmium." The Danube and the Save were held by the enemy, and the Emperor had no army, but through Illyria and Dalmatia officers were sent to conduct the defence. On the islands of Casia and Carbonaria Theognis met the Khagan, but negotiations were fruitless. For two years, despite fearful hardships, the city resisted, but the governor was incompetent, and the troops under Theognis inadequate, and at last, some short time before his death, Tiberius, to save the citizens, sacrificed Sirmium. The inhabitants were granted life, but all their possessions were left in the hands of the barbarians, who also exacted the sum of 240,000 nomismata as payment for the three years' arrears (580-582) due under the terms of the former agreement which was still to remain in force.
It was during the investment of Sirmium that the Slavs seized their golden hour. They poured over Thrace and Thessaly, scouring the Roman provinces as far as the Long Walls — a flood of murder and of ravage: the black horror of their onset still darkens the pages of John of Ephesus.
In the year which saw the fall of Sirmium (582) Tiberius died. Feeling that his end was near, on 5 Aug. he created Maurice Caesar and gave
