The Byzantines captured Qurus (Cyrrhus) in July 906, destroying the city and carrying off its inhabitants. In October 906, Ahmad ibn Kayghalagh and Rustam ibn Baradu launched a raid that reached as far as the Halys River before turning back laden with spoils and captives. On the sea, Himerios won a victory over an Arab fleet on St. Thomas's day, 6 October 906. In spring 907, however, Andronikos Doukas and his son Constantine defected to the Abbasids, the victims of the intrigues of Leo VI's powerful eunuch chamberlain, Samonas. One notable and unique case of al-Muktafi's diplomatic relations are his correspondence with Bertha, daughter of the King of Lotharingia and wife of Adalbert II, Margrave of Tuscany. In 906, Bertha sent a letter, written in Latin, and rich gifts to al-Muktafi, seeking his friendship and a marriage alliance. Bertha was apparently motivated by the threat posed by the Arab colony at Fraxinetum, and turned to al-Muktafi in the—mistaken—belief that the caliph still exercised real power over the Aghlabid rulers of Ifriqiya. Al-Muktafi in turn replied with a letter of his own, but nothing came of this long-distance correspondence. Death and legacy Al-Muktafi was a successful ruler, as well as "a man of sensibility, a gourmet and an appreciator of the verses of poets like Ibn al-Rumi". As the historian Harold Bowen writes, "the Caliphate seemed in his day almost to have regained its former glory", having overcome the Qarmatian challenge and regained Egypt and Syria. His fiscal policies, building upon those of his father, also ensured prosperity and a full treasury, despite the drain and devastation of continuous warfare. Al-Muktafi, however, was of a sickly disposition since childhood; indeed, he may have been ill for much of his reign. In late spring 908 he fell gravely ill, and for about three months, the caliph lay incapacitated, his situation alternately improving and deteriorating. It soon became clear, however, that he would not survive his illness. Al-Muktafi had nine sons, but they were all underage, and due to his illness, he was unable to determine a successor. The vizier, al-Abbas al-Jarjara'i, sounded out the leading officials of the bureaucracy on the issue—an unprecedented act that demonstrated the monopoly of power now exercised by the civilian bureaucrats. Muhammad ibn Dawud al-Jarrah favoured the experienced and capable Abbasid prince Abdallah ibn al-Mu'tazz, but the vizier eventually followed the advice of Ali ibn al-Furat, who