Earlier, Rome had had a commander of the horse soldiers (equites), called a Magister equitum, and a commander of the infantry (pedites), called a Magister peditum. A commander in charge of both was known as the Magister utriusquae militiae. Magister...praesentalis was a commander in the presence of the emperor.
For information on civil and military titles, see Notitia Dignitatum and "The Roman Magistri in the Civil and Military Service of the Empire," by A. E. R. Boak. Harvard Studies in Classical Philology, Vol. 26, (1915), pp. 73-164.


