promised that he would never support his uncle. Even so, Emperor Manuel allowed the dethroned king to stay in Sirmium. In short, Stephen III invaded Dalmatia, although he had pledged to Vitale II Michiel, Doge of Venice, that he would withdraw from the Dalmatian towns. Upon Stephen's arrival the citizens of Zadar expelled the Venetian governor and accepted his suzerainty. He again stormed into Sirmium and laid siege to his uncle in Zimony in spring 1165. Emperor Manuel decided to make a counterattack, but a rebellion by his cousin Andronikos Komnenos prevented him from marching to the Danube. Nevertheless, Manuel I sent envoys to the monarchs who had earlier supported Stephen III, persuading them to remain neutral in the conflict. Stephen III's uncle died of poisoning during the siege of Zimony, on 11 April. The fortress soon fell to Stephen III. The Byzantine counter-offensive started at the end of June. An army under the command of Emperor Manuel I laid siege to Zimony and recaptured it; another Byzantine force invaded and occupied Bosnia and Dalmatia. The Venetian fleet intervened on the Byzantines' side in Dalmatia, forcing Zadar to again accept the rule of the Doge. Stephen III could only conclude a new peace treaty with Emperor Manuel after he renounced Sirmium and Dalmatia. A Hungarian army under the command of Ispán Denis stormed into Sirmium once more in spring 1166. The Hungarians routed a Byzantine army, and occupied the whole province with the exception of Zimony. Emperor Manuel sent three armies against Hungary. The first army, which was under the command of protostrator Alexios Axuch and Stephen III's brother, Béla, was stationed by the Danube to distract attention from the movements of the two other units, which plundered Transylvania under the command of Leon Batatzes and John Doukas. The Byzantine campaign caused great devastation in the eastern territories of the Kingdom of Hungary, forcing Stephen III to seek reconciliation. Upon his request, Henry Jasomirgott, Duke of Austria, whose wife was Emperor Manuel's niece, mediated an armistice. At the end of the year, Stephen married the Duke's daughter Agnes. Around the same time, a Hungarian army invaded Dalmatia and captured Nikephoros Chalouphes, the Byzantine governor of the province. Stephen confirmed estates in Biograd na Moru and the privileges of Šibenik in 1166 and 1167, respectively, proving that the two towns accepted his suzerainty after the campaign. Emperor Manuel dispatched an army