caliph
The supreme religious and political authority of Muslims, considered successor of Muhammad (Arabic: khalifa = deputy). He was the head of the Caliphate, the religious state of the Arabs.

domestikos ton scholon
Commander of the regiment of scholae. The first officer with this title appears in 767/8. In the 10th C the domesticos became very powerful among the army of the themata; in mid-10th C the office was divided in two, domestikoi ton scholon of the East and those of the West, commanders in chief of the eastern and the western provinces´ army respectively.

magistros
Higher office that Philotheos in his Kletorologion places above the anthypatos. This title lost its importance from the 10th century and gradually disappeared - most probably in the middle of the 12th century.

strategos ("general")
During the Roman period his duties were mainly political. Οffice of the Byzantine state´s provincial administration. At first the title was given to the military and political administrator of the themes, namely of the big geographic and administrative unities of the Byzantine empire. Gradually the title lost its power and, already in the 11th century, strategoi were turned to simple commanders of military units, responsible for the defence of a region.