In 1147 the Byzantine empire under Manuel I Comnenus was faced with war by Roger II of Sicily, whose fleet had captured the Byzantine island of Corfu and plundered Thebes and Corinth. However, despite being distracted by a Cuman attack in the Balkans, in 1148 Manuel enlisted the alliance of Conrad III of Germany, and the help of the Venetians, who quickly defeated Roger with their powerful fleet.