Иоанн Дука
After Manzikert, the Byzantine government sent a new army to contain the Seljuk Turks under Isaac Komnenos, a brother of the future emperor Alexios I Komnenos, but this army was defeated and its commander captured in 1073. The problem was made worse by the desertion of the Byzantines' western mercenaries, who became the object of the next military expedition in the area, led by the "Caesar" John Doukas. This campaign also ended in failure, and its commander was likewise captured by the enemy. The victorious mercenaries now forced John Doukas to stand as pretender to the throne. The government of Michael VII was forced to recognize the conquests of the Seljuks in Asia Minor in 1074, and to seek their support. A new army under Alexios Komnenos, reinforced by Seljuk troops sent by Malik Shah I, finally defeated the mercenaries and captured John Doukas in 1074.