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• The Works of Edward Gibbon
• The History of the Decline and Fall of the Roman Empire
• Chapter Xvi
• Chapter Xvii
• Chapter Xviii
• Chapter Xix
• Chapter Xx
• Chapter Xxi
• Appendix Additional Notes By the Editor
• 1.: The Rescript of Antoninus Concerning the Christians — ( P. 30 )
• 2.: Exile of Marcellus and Eusebius, Bishops of Rome — ( P. 77 )
• 3.: Persecutions of the Christians In the First and Second Centuries, — ( C. Xvi .)
• 4.: Augusteum and Forum of Constantine — ( P. 104-106 ) 1
• 5.: The New Monarchy — ( C. Xvii .)
• 6.: Dioceses and Provinces — ( P. 126 Sqq. )
• 7.: The Organisation of the Army Under the New System — ( P. 136 Sqq. )
• 8.: Protectores and Domestici — ( P. 150 )
• 9.: The Tragedy of Fausta and Crispus — ( P. 175 Sqq. )
• 10.: Divisions of the Empire, 293 to 378 — ( P. 183 , 196 )
• 11.: The Sarmatians — ( P. 186 )
• 12.: Battle of Singara — ( P. 200 )
• 13.: Sources and Chronology of Armenian History Under Trdat and His Successors — ( C. Xix .)
• 14.: Constantine and Christianity — ( C. Xx .)
• 15.: Ecclesiastical Geography — ( P. 314 )

7.

THE ORGANISATION OF THE ARMY UNDER THE NEW SYSTEM — (

P. 136

sqq.)

Mommsen has brought light and order into the subject of the new military organisation which was introduced in the epoch of Diocletian and Constantine, by his article entitled Das römische Militärwesen seit Diocletian, which appeared in Hermes in 1889 (vol. xxiv. p. 195 sqq.). The following brief account is based on this important study.

Under Diocletian the regular army seems to have fallen into two main divisions: the troops who followed the emperor as he moved throughout his dominion, and the troops stationed on the frontier. The latter were called limitanei, the former were possibly distinguished as in sacro comitatu (cp. C.I.L. 3, 6194). But early in Constantine’s reign the troops in sacro comitatu were broken up into two classes, the comitatenses and the Palatini (before 310, for the comitatenses existed then, cp. C.I.L. 5565; palatini occurs first in a law of 365 , Cod. Theod. vii. 4, 22). Thus there were three great divisions of the army: 1, (a) palatini, (b) comitatenses, and 2, limitanei. Thus Gibbon’s use of palatines to include the comitatenses is erroneous.

The other most important changes introduced by Constantine were: the increase of the comitatenses (who were under the command of the magister militum) at the expense of the limitanei, who had been increased by Diocletian; and the separation of the cavalry from the infantry.

1. Limitanei (commanded by duces). The statement that Diocletian strengthened the frontier troops (Zos. ii. 34) is borne out by the fact that if we compare the list of the legions in the time of Marcus (C.I.L. 6, 3492) with the Notitia Dignitatum, we find in the former twenty-three legions, in the latter the same twenty-three and seventeen new legions (leaving out of account Britain, Germany, Africa, for which we have not materials for comparison). And if we remember that Constantine drafted away regiments (the pseudo-comitatenses) to increase his comitatenses, we may conclude that Diocletian doubled the numbers of the frontier armies.

The limitanei consisted of both infantry and cavalry. (1) The infantry consisted of legiones, auxilia, and cohortes. (a) The legions are of two kinds. The old legions of the Principate retain their old strength of 6000 men; while the new legions correspond to the old legionary detachments, and are probably 1000 strong. But the larger legions are usually broken into detachments which are distributed in different places, and the præfectus legionis consequently disappears. (b) The auxilia are of barbarian formation, and as such are thought more highly of than the rest of the frontier infantry; they are found only in the Illyric provinces. The size of the auxilium is probably 500. (c) The cohortes, 500 strong as under the Principate, are found everywhere except in the duchies on the Lower Danube. (2) The (a) cunei equitum probably differ from (b) equites, by being of barbarian formation and of higher rank. The (c) ala is generally 600 (not as before 500) strong.

Constantine’s new organisation reduced the limitanei to second-class troops, as compared with the imperial troops of both kinds.

2. Imperial Troops. (a) Comitatenses (under Masters of Soldiers) consist of infantry and cavalry: (α) The legion is of the smaller size, about 1000 strong; (β) the vexillatio of horse is about 500 strong. Connected with the comitatenses but of lower rank are the pseudo-comitatenses, drawn from the frontiers (eighteen legions in the west, twenty in the east). (b) Palatini (under Masters of Soldiers in præsenti) consist of infantry and cavalry: (α) the legion of 1000; (β) the vexillatio of 500.

In connection with the Palatini, the auxilia palatina demand notice. These are troops of light infantry, higher in rank than the legion of the comitatenses, lower than the palatine legion. They chiefly consist of Gauls and include Germans from beyond the Rhine (but virtually no orientals). Mommsen makes it probable that their formation was mainly the work of Maximian (p. 233). They were perhaps the most important troops in the army.

The scholae, which seem to have been instituted by Constantine, must also be mentioned here (cp. Cod. Theod. 14, 17, 9). They were probably so called from having a hall in the palace to await orders. At first they were composed of Germans (but in fifth century under Leo I., of Armenians; under Zeno, of Isaurians; afterwards of the best men who could be got, Procop., Hist. Arc. c. 24). There were at first five divisions of 500 men; then seven; finally under Justinian eleven. The division was commanded by a tribune, who was a person of much importance (e.g., Valentinian I.). They ultimately lost their military character, and the excubitores (first introduced by Leo I.) took their place.

Gibbon considers the question of the size of the army under the New Monarchy. On one side, we have the fact that under Severus at the beginning of the third century there were thirty-three legions, which, reckoned, along with their adjuncts, at the usual strength, give as the total strength of the army about 300,000. On the other side we have the statement of Agathias quoted by Gibbon, which puts the nominal strength of the army in the middle of the sixth century at 645,000. Taking into account the great increase of the troops under Diocletian, the record that the army was further strengthened by Valentinian (cp. Amm. Marc., 30, 7, 6, Zos. 4, 12), and a statement of Themistius (Or. 18, p. 270) as to the strength of the frontier forces under Theodosius the Great, we might guess that at the beginning of the fifth century, when the Notitia was drawn up, the army numbered five, if not six, hundred thousand. These a priori considerations correspond satisfactorily with the rough calculation which Mommsen has ventured to make from the data of the Notitia. His figures deserve to be noted, though he cautions us that we must not build on them.

A word must be said about the gentes, who, outside the Roman provinces and formally independent, but within the Roman sphere of influence and virtually dependent on the Empire, helped to protect the frontiers and sometimes supplied auxiliary troops to the Roman army. (Thus in Amm. xxiii. 2, 1, we read of legationes gentium plurimarum auxilia pollicentium; Julian refuses such adventicia adiumenta.) The most important of these gentes are the Saracens on the borders of Syria, and the Goths on the right bank of the Danube. They are fæderati; and their relation to the Empire depends on a fædus which determines the services they are bound to perform. Under the Principate the theory was that such fæderati were tributaries, but in return for their military services the tribute was either remitted or diminished. But under the new system, they are considered rather in the light of a frontier force and, like the regular riparienses, are paid for their work. Consequently the amount of the annonæ fæderaticæ is the chief question to be arranged in a fædus. The Lazi of Colchis were an exception to this rule; though federates they received no annonæ (Procop., B. P. 2, 15). The inclusion of the federates in the Empire is illustrated by the treaty with Persia in 532 , in which the Saracens are included as a matter of course, without special mention (Procop., B. P. 1, 17; 2, 1). See Mommsen, op. cit. p. 215 sqq.