The original command structure of the late Roman army, with a separate magister equitum and a magister peditum in place of the later overall magister militum in the command structure of the army of the Western Roman Empire.
The high command structure of the West Roman army c. 410–425, based on the Notitia Dignitatum

Magister militum (Latin for "master of soldiers"; pl.: magistri militum) was a top-level military command used in the late Roman Empire, dating from the reign of Constantine the Great. The term referred to the senior military officer (equivalent to a war theatre commander, the emperor remaining the supreme commander) of the empire. In Greek sources, the term is translated either as strategos or as stratelates (although these terms were also used non-technically to refer to commanders of different ranks).

Establishment and development of the command

Further information: Late Roman army

Iovinus was magister equitum from 361 to 369 under several Roman emperors, from Julian to Valentinian I. Accordingly, he had himself depicted on his richly decorated marble sarcophagus as a fighting equestrian general (centre). Musée Saint-Remi, Reims.

The office of magister militum was created in the early 4th century, most likely when the Western Roman emperor Constantine the Great defeated all other contemporary Roman emperors, which gave him control over their respective armies. Because the Praetorian Guards and their leaders, the Praetorian Prefects, had supported Constantine's enemy, Maxentius, he disbanded the Guard and deprive the Prefects of their military functions, reducing them to a purely civil office. To replace them, he created two posts, one as head of the infantry, as the magister peditum ("master of foot"), and one for the more prestigious cavalry, the magister equitum ("master of horse"). These offices had precedents in the immediate imperial past, both in function and idea.[1] The latter title had existed since republican times, as the second-in-command to a Roman dictator.

Under Constantine's successors, the title was also established at a territorial level: magistri peditum and magistri equitum were appointed for every praetorian prefecture (per Gallias, per Italiam, per Illyricum, per Orientem), and, in addition, for Thrace and, sometimes, Africa. On occasion, the offices would be combined under a single person, then styled magister equitum et peditum or magister utriusque militiae ("master of both forces"). Overall, magistri were employed and utilized according to circumstances. Sometimes more or fewer generals would be employed in a given area.[2]

As such they were directly in command of the local mobile field army of the comitatenses, which acted as a rapid reaction force. Other magistri remained at the immediate disposal of the emperors, and by the late fourth century or early fifth century were termed in praesenti ("in the presence" of the emperor).

Over the course of the fourth century in the Western Roman Empire the system of only two magistri remained largely intact, with usually one magister having paramount authority, for example Merobaudes, who was the main power behind the appointment of emperor Valentinian II, and then Bauto. Finally, Arbogastes inherited the position of western magister militum and controlled emperor Valentinian II from behind the scenes, either killing him or driving him to suicide before appointing his own puppet emperor, Eugenius. Such a powerful position continued in the west often with the title of magister utriusque militiae (abbreviated MVM), and was held by Stilicho, Aetius, Ricimer, and others.

In the east, emperor Theodosius I (379-395) expanded the system of two magistri militum to include an additional three magistri. For a long time these generals were used in an ad hoc manner, being employed wherever they were needed. Eventually in the fifth century their positions became more firmly established, and there were two senior generals, who were each appointed to the office of magister militum praesentalis.

During the reign of Emperor Justinian I, with increasing military threats and the expansion of the Eastern Empire, the posts of the eastern generals were overhauled: the magister militum per Armeniam in the Armenian and Caucasian provinces, formerly part of the jurisdiction of the magister militum per Orientem, the magister militum per Africam in the reconquered African provinces (534), with a subordinate magister peditum, and the magister militum Spaniae (c. 562).

In the course of the 6th century, internal and external crises in the provinces often necessitated the temporary union of the supreme regional civil authority with the office of the magister militum. In the establishment of the exarchates of Ravenna and Carthage in 584, this practice found its first permanent expression. Indeed, after the loss of the eastern provinces to the Muslim conquest in the 640s, the surviving field armies and their commanders formed the first themata.

Supreme military commanders sometimes also took this title in early medieval Italy, for example in the Papal States and in Venice, whose Doge claimed to be the successor to the Exarch of Ravenna.

List of magistri militum

Unspecified commands

Comes et magister utriusque militiae

Per Gallias

Per Hispanias

Per Ilyricum

Per Orientem

Per Armeniam

Per Thracias


Per Africam

Western Empire

Eastern Empire

Magister militae in Byzantine and medieval Italy


Later, less formal use of the term

By the 12th century, the term was being used to describe a man who organized the military force of a political or feudal leader on his behalf. In the Gesta Herwardi, the hero is several times described as magister militum by the man who translated the original Old English account into Medieval Latin. It seems possible that the writer of the original version, now lost, thought of him as the hereward' (Old English: here, lit.'army' and no: weard, lit.'guard') – the supervisor of the military force. That this later use of these terms was based on the classical concept seems clear.[27]

See also



  1. ^ Bendle, Christopher (2024). The office of "Magister Militum" in the 4th century CE: a study into the impact of political and military leadership on the later Roman Empire. Studies in ancient monarchies. Stuttgart: Franz Steiner Verlag. p. 31. ISBN 978-3-515-13614-3.
  2. ^ Bendle, 2024. 31.
  3. ^ a b c d e f g h i j k PLRE I, p. 1114
  4. ^ PLRE I, p. 62
  5. ^ Hughes, Ian: Aetius: Attila's Nemesis, p. 74
  6. ^ Hughes, Ian: Aetius: Attila's Nemesis, p. 75
  7. ^ Hughes, Ian: Aetius: Attila's Nemesis, p. 85
  8. ^ Hughes, Ian: Aetius: Attila's Nemesis, p. 87, Heather, Peter: The Fall of the Roman Empire, pp. 262, 491
  9. ^ a b c d e f g h i j k l m PLRE I, p. 1113
  10. ^ Hydatius, Chronica Hispania, 122
  11. ^ Hydatius, Chronica Hispania, 128
  12. ^ Hydatius, Chronica Hispania, 134
  13. ^ a b c d PLRE I, p. 1112
  14. ^ PLRE I, p. 125
  15. ^ PLRE I, p. 307
  16. ^ Jones, Arnold Hugh Martin; Martindale, J. R.; Morris, J. (1980). The Prosopography of the Later Roman Empire: Volume 2, AD 395–527. Cambridge University Press. p. 228. ISBN 9780521201599.
  17. ^ Martindale, J. R. (1992). The Prosopography of the Later Roman Empire 2 Part Set: Volume 3, AD 527–641. Cambridge University Press. p. 845. ISBN 978-0-521-20160-5.
  18. ^ Greatrex, Geoffrey; Lieu, Samuel N. C. (2005). The Roman Eastern Frontier and the Persian Wars AD 363–628. Routledge. ISBN 978-1-134-75645-2.
  19. ^ Kaegi, Walter Emil (2003). Heraclius, Emperor of Byzantium. Cambridge University Press. p. 22. ISBN 978-0521814591.
  20. ^ PLRE II, p. 597
  21. ^ PLRE II, p. 211
  22. ^ PLRE I, pp. 1113–1114
  23. ^ PLRE I, p. 152
  24. ^ John Moorhead, Justinian (London, 1994), p. 16.
  25. ^ John Moorhead, Justinian (London, 1994), p. 17.
  26. ^ PLRE I, p. 395
  27. ^ Gesta Herwardi Archived 2011-01-21 at the Wayback Machine The term is used in chapters XII, XIV, XXII and XXIII. See The Name, Hereward for details.