The first point to notice in this list is the smallness of the contingent from the senatorial provinces. So small is it that Mommsen desired to see here evidence of a constitutional principle.[179] The auxilia were ‘gewissermassen eine Hausmacht des Kaisers’ and as such raised only in the provinces governed by his legati. Such instances as were then known of regiments raised in senatorial provinces were, he thought, susceptible of explanation. The alae Vocontiorum, for instance, represented a civitas foederata which was not, strictly speaking, a part of the senatorial province of Narbonensis. It does not, however, seem possible to maintain this theory. The Cohors I Cretum[180] is a certain case of a regiment from a senatorial province, nor can it be really doubted that contingents were also drawn from Cyprus[181] and Cyrene.[182] Indeed, it is difficult to see what legal or political obstacle should prevent Augustus and his successors from utilizing the military material available in the senatorial provinces. Even if Mommsen is right in believing that conscription, as opposed to the enrolment of volunteers, could only take place in a senatorial province with the authority of the Senate (and this theory is questioned by both Gardthausen and Liebenam),[183] there is no reason why levies should not have been made for the auxilia under these conditions when they certainly were made for the legions.[184] In no case did any military power remain in the hands of the Senate, since the recruits would immediately be marched away to garrison imperial provinces. As a matter of fact, the reason for the smallness of the senatorial contingent seems to have been a practical one. Few auxilia were raised from Narbonensis and Baetica, because the greater part of the inhabitants of these provinces had received the franchise and were consequently eligible for service in the legions. Achaia, Asia, and to a certain extent Macedonia, were treated as being on the same footing, partly because Greeks did actually serve in the Eastern legions, partly because of the Philhellenic policy of the imperial government, which would not deny to the Greek states, although they were technically unenfranchised, the privileges enjoyed by the enfranchised urban communities of the West. Also no doubt the Greek of the period was not rated highly as a fighting man. On the other hand, from Cyrenaica, Crete, Cyprus, parts of Macedonia, and Africa[185] useful troops could be and were obtained. The way in which the system worked is shown by the case of Noricum, which, although an imperial province, included many enfranchised communities and contributed recruits to the Rhine legions in the middle of the first century.[186] Its contribution of auxilia in consequence is limited to one ala and one cohort, as against the eighteen regiments furnished by the neighbouring province of Raetia.
In contrast to Narbonensis, it was upon the remaining three Gallic provinces that the levy fell most heavily. From this district came more than a quarter of the auxiliary infantry[187] in the pre-Flavian period and nearly half the cavalry. The Gallic troopers indeed maintained for a century the reputation which they had won under Caesar’s command, and Strabo,[188] writing in the reign of Augustus, places them above all other cavalry in the imperial army. Arrian,[189] too, notes their reputation and the number of Celtic words in the cavalry drill-book, although in his day their position had been taken by the Pannonians, already prominent in the campaign of 69.[190] Spain sent the largest contingent after the Gallic provinces, and also contributed a few words to the drill-book,[191] but we hear nothing of the quality of the Spanish troops and they soon lost their early importance. The predominance of the auxilia of Spain and Gaul in the pre-Flavian period is, however, a clear indication of the determination of Augustus to base the Empire on its Western provinces. Archers alone, and these in comparatively small numbers, were drawn from the East,[192] which was still regarded as the home of dangerous and un-Roman ideals.
Lastly, a word must be said about a group of regiments which do not appear in the above lists and are too numerous to be passed over. These are the cohorts which bear the titles voluntariorum civium Romanorum, ingenuorum c. R., Italica c. R., and campestris.[193] Collectively these regiments constitute the cohortes civium Romanorum to the soldiers of which Augustus left by his will a donative equal to that of the legionaries.[194] From various passages in the literary authorities it appears that they represent the result of two levies made by Augustus in Italy, the first during the Pannonian rising, and the second after the defeat of Varus.[195] When free-born citizens could not be found in sufficient numbers the levy was extended to freedmen.[196] This is corroborated by the evidence of the inscriptions, since the title ingenuorum clearly implies the existence of regiments whose members could not make this boast.[197] Originally, as the provisions of the will of Augustus show, these cohorts occupied a peculiar position, and were practically on a level with the legionaries, in consequence of which their commanders bear the title of tribunus.[198] The presence, however, of the Cohors VIII Voluntariorum on the Dalmatian diploma of 93 shows that unenfranchised recruits had been accepted even during the pre-Flavian period, and in the following century only their title distinguishes these regiments from the ordinary auxilia.
The evidence hitherto considered has mainly served to illustrate the original distribution of the burden of military service and the respective quotas furnished by the different provinces to the auxilia at the time of their organization. To trace the further workings of this system it is necessary to examine the principles on which the auxiliary regiments were distributed among the military areas and to trace the relations between this distribution and the method of recruiting.
A casual glance at the military diplomata, which give a fair idea of the composition of the more important provincial garrisons between the reign of Vespasian and that of Commodus, suggests that it was the settled policy of the imperial government to destroy the possibility of national cohesion and local sympathies among the regiments raised from their subjects by distributing the contingents of each recruiting district over as wide an area as possible, and making every frontier army corps a mosaic of different nationalities. It will be shown later that this theory, which has been frequently adopted by modern writers, will not stand before a closer scrutiny of the evidence as an explanation of the state of things existing in the second century; it can also be shown that such a principle of distribution was not the original policy inaugurated by Augustus.
Our earliest evidence relates to the composition of the garrison of the Danubian provinces, and the account of the great rising which took place here in the year A.D. 6 by the contemporary observer Velleius makes it clear that the strength of the rebels lay in the training which many had received in the Roman army. His reference to the military knowledge of the leaders and the discipline of the rank and file indicates that regular auxiliary regiments, raised locally and stationed near their homes, had mutinied in sympathy with their fellow tribesmen.[199] Concerning the state of things on the Rhine frontier we have more detailed information which points to the same conclusion. The account in the Annals of the campaigns of Germanicus mentions cohorts of Raeti, Vindelici, and Gauls in addition to the tumultuariae catervae of the local militia.[200] Later in the century we find an Ala Treverorum engaged in putting down a revolt of their own countrymen in 21,[201] an Ala Canninefatium engaged in the disastrous expedition of L. Apronius against the Frisii in 28,[202] and Vangiones and Nemetes helping to repulse a raid of the Chatti in 50.[203] Finally, when we turn to the narrative contained in the Histories of the events of the disastrous year 69, we find abundant evidence that at this date three-fourths of the Rhenish auxilia were drawn from Gaul proper or the Teutonic tribes of Belgica. The only regiments mentioned by Tacitus which are not of local origin are (1) Thracians, who appear on every frontier owing to their special qualifications as archers;[204] (2) Spaniards, who may have entered the province in 43 with Legio IV Macedonica, which was transferred from Spain to the Rhine to replace the troops sent to Britain, and (3) Britons, who probably began to arrive from the newly conquered areas a few years later.[205] Epigraphical evidence adds to the list a few regiments from the Danubian provinces and some corps of oriental archers.[206]
In other provinces the same policy can be traced, although the evidence is less abundant. In Africa, for example, the deserter Tacfarinas seems to have served in his own province,[207] and in Palestine we find Samaritan regiments garrisoning Caesarea.[208] On the whole there is sufficient evidence to show that although each of the great frontier armies contained imported elements, in particular the ubiquitous Thracian and oriental archers, the original policy of the imperial government was to draw the auxilia in each case from the nearest recruiting-areas.
Both the advantages and the defects of this system are sufficiently obvious. It saved trouble, a reason which had already commended it to the administrators of the Republic, and it avoided the dangerous and widespread discontent which, as the case of the Thracians shows, would have followed any wholesale attempt to remove the newly organized regiments to distant provinces.[209] Lastly, the men would be fighting on ground which they knew against an enemy with whose methods of fighting they would already be acquainted. On the other hand, there was of course the obvious danger that in a border war which assumed the character of a national struggle the local auxilia might desert to their own countrymen and use the training which they had acquired in the Roman service to increase the strength of the hostile resistance. As a set-off to this danger the Romans reckoned with some justice that tribal enmity was usually stronger than national feeling, and in fact there were many tribal chiefs like Flavus, the brother of Arminius, who were well content with the rewards and distinctions which recompensed their fidelity.[210] Events, however, made it clear that this confidence was misplaced. A time was to come when the border tribes would identify themselves readily with the cause of imperial defence, but the influences which were to bring about this result were often slow in their operation, and the first century saw on almost every frontier a more or less serious outbreak of national feeling, in which the auxilia often participated. Yet even the most serious of these revolts, that of Civilis in 69, showed how the new leaven was working. The political conceptions of the mutineers were borrowed from their conquerors, not from their ancestors, and in the darkest hour of the revolt a Gallic cavalry regiment, the Ala Picentiana, was the first to return to its fidelity.[211]
The first district in which the Augustan policy broke down was the Danubian provinces, and a glance at the names of the regiments stationed here in the pre-Flavian period shows that the lesson of the great rebellion was not thrown away upon the imperial authorities. In Pannonia a diploma of the year 60[212] shows us the following seven cohorts, I and II Alpinorum, I Asturum et Callaecorum, I and II Hispanorum, I Lusitanorum, and V Lucensium et Callaecorum, forming part of the garrison of the province, and we may add the Ala Aravacorum on the strength of an early inscription.[213] In Dalmatia early inscriptions give the following cohorts:
I Campanorum Voluntariorum civium Romanorum. iii. 8438.