The term "secret service" has several definitions. It can mean the detective service of government, a police force concerned with the internal security of the state, and when used to describe an institution of the Roman Empire, it may thus suggest the image of an ancient Gestapo, NKVD, or FBI. Actually, the resemblance between the Roman internal security police force and its modern counterparts, while close in some important particulars, is by no means complete. Accordingly, the expression "secret service" should be conceived as a convenient, if not perfectly descriptive, label for an ancient institution which has no exact modern parallel.
A secret service developed rather late in Roman history for several reasons. First of all, the idea of a permanent, highly organized agency of this nature was foreign to principles of city-state government common to classical Greece and republican Rome. In the absence of an attorney general's office, both the Greeks and early Romans preferred to rely on citizen informers and prosecutors to reveal threats aganist the state. (1) The Spartans, it is true, had a secret service of sorts, the krypteia, but that was a by-product of the unique problem posed by helotry. (2) Of greater interest than the krypteia is the Persian intelligence agency, "the eyes and ears of the King", a true detective service which attracted the attention and admiration, but not the emulation, of the Greeks. (3) It might be expected that the Romans, faced by the second century B.C. with the problem of governing distant provinces like the Persians before them, should have borrowed or discovered such a centralizing institution. They did not, partly because the absolutism inherent in a secret service ran counter to ideals of government by senatorial oligarchy, partly because the bureaucracy, of which any sophisticated secret service is but a function, was still in an embryonic stage of development. (4)
It is significant that the first prototypes of the Roman secret service appeared in the period of civil wars which destroyed the Republic during the last century of its existence. During that era, warring dynasts turned to trusted soldiers, sometimes chosen from their private military entourage or praetorian guard, to ferret out information and, as officers of arrest or execution to do the "dirty work" that one might expect of a secret police. (5)
Even before his accession to sole power, Augustus was well versed in the use of trusted personnel on such missions. (6) It was characteristic of Augustus, as self-proclaimed restorer of the Republic and as princeps, that he masked imperial absolutism, and so it is not surprising that little knowledge has survived of practices protecting the security of the state and of its chief during his reign. It seems certain, however, that Augustus and his successors during the first century of the Empire did not rely on any one agency in particular to detect and to expose subversion.
They used informers - delatores - to reveal a wide range of crimes, real and imagined. (7) One should perhaps stress that the Romans throughout their history made great use of informers and that they became an important supplement to an institutionalized secret service. Delation is a constant factor in the history of internal security not only during the Republic, but throughout both the Principate and Late Empire. In addition to informers, the first emperors used efficiently the praetorian guard, especially its centurions and tribunes, to act as plain-clothes men and to arrest those accused of treason. (8) Sometimes they depended upon highly placed freedmen at court or on provincial procurators to gather confidential information. (9)
The agency that was to deserve the title of secret service first came into existence at some time shortly before A.D.100, and one may with some confidence attribute its foundation to Domitian. (10) The Roman secret service probably developed out of a basic reform instituted by Domitian in the "G-4" or supply section of the imperial general staff - the praetorium - and involving the use of non-commissioned officers and some centurions. Stated simply, the Roman secret service was staffed by supply sergeants whose original functions had been the purchase for and distribution to the troops of grain - frumentum - whence their name, frumentarii. (11) It seems probable that frumentarii or their prototypes had been serving on the headquartes staffs of governors-general even before Domitian's reign, although there is no positive evidence that this was the case. Commentators assume that they were on the move on logistical assignments at an early date, and that they were in constant touch not only with the army and bureaucracy, but with the provincial population as well. Hence they were in an excellent position to observe and to report on all kinds of situations of interest to the government. Domitian was probably the first to recognize that they could be an excellent liaison between the provinces and the general staff at the capital, and to detach some of them from their legionary headquarters for temporary duty as couriers in the service of "G-4" at Rome. He probably founded for them, and for other non-commissioned officers similarly seconded from the provinces, a special transient billet and base of operations on the Caelian hill, the castra peregrinorum. (12) The frumentarii who were thus placed for a time at the disposal of the central government were still carried on the strength of their provincial legions, even though they had been shifted into a different chain of command. Their headquarters at Rome was commanded by a senior centurion, the princeps peregrinorum, who was responsible directly to the emperor, or, in his place, to the praetorian prefecture. (13)
The frumentarii, soldiers like many early imperial bureaucrats, were perfectly integrated into the Roman military establishment by virtue of their recruitment, careers, and functions. If any fairly close parallel is to be drawn between them and any modern American institution, it is to be found in the organization, if not in the duties, of Military Intelligence rather than in the FBI. Although of unusual importance to the central government, they tended to blend into Roman military administration, in which their position appears to the modern observer deceptively routine.
It is sometimes stated that these agents were recruited exclusively from the western provinces, at least before the Severan dynasty, the implication being that they were "more Roman", more suited to employment as centralizers of the government, perhaps as some sort of elite corps or Roman SS. (14) Such a view rests on a basic misconception of Roman military and administrative policy and is demonstrably false. (15) All legions sent frumentarii to Rome for special duty; for this reason, the frumentarii may be regarded from the point of view of their recruitment as a typical microcosm of the imperial non-commissioned officers' cadre. Like the legionaries in general, the frumentarii of the second and third centuries tended to be recruited locally by the various provincial garrisons. (16) They ranged from men of lowly origin and of possibly doubtful Latinity and Romanizations (17) to the sons of the municipal middle classes who possessed much higher standards of culture and education. (18)
From the point of view of their careers as well as of their recruitment, the frumentarii were typical enlisted men. That is to say, they had very little chance of rising high in the military or administrative hierarchy. (19) Some held other administrative posts as non-commissioned officers before death or retirement; (20) some reached the centurionate, (21) but few of them who rose from the ranks were promoted into the equestrian hierarchy of office-holding. The chances for speedier advancement were greater if a man had been commissioned a centurion directly upon recruitment and had served as frumentarius in that rank. In such a case fast advancement probably depended more on his having begun as a centurion at an early age than on his having been employed in the secret service. (22) Even with the advantage of original recruitment as a centurio frumentarius, one could not look forward to ending one's career as more than an equestrian governor of some fairly small and insignificant province, albeit at an excellent sal
ary. (23) Only during the Severan dynasty do former secret service agents, and these rather few, attain the highest honors as praetorian prefects, senators, or even, in one case, as consular colleague of the emperor. (24) Such promotion was regarded by contemporaries as unusual and scandalous. (25) Plainly, then, a career in the secret service was not necessarily more promising than any other for the Roman non-commissioned officer.
No table of military strength and organization has survived to indicate how many of these agents were on the rolls of each legion. It was once thought that a typical governor's staff contained only one frumentarius, but such a view is unattested by the sources and is improbable. (26) An estimate of their number can be made, since the approximate size of legionary staffs is known, as well as the number of various other military bureaucrats serving on them. (27) In the second century A.D. each legion probably supplied something on the order of five or ten frumentarii, which would give a total strength in the provinces and on duty at the capital of about two hundred men. (28) This number need not have been static, and an increase may be posited for the third century as the central government was increasingly preoccupied in areas where the frumentarii could render invaluable service: communication, supply and taxation, and internal security.
The Roman army in general and its secret service in particular regarded the state highway network with its way and posting stations, the military supply and taxation systems, which depended on the roads, and the various military posts which guarded them and the surrounding countryside as an integrated unit. (29) It is not surprising, therefore, to discover that the three basic duties of the secret service were those of couriers, tax collectors, and policemen. There is positive evidence that the frumentarii, as couriers bearing all kinds of messages to and from the central government, were among the most important users of the state highways. As such, they could requisition horses, carriages, lodging, and supplies which were at the disposal of officials on state business. (30) As couriers they resembled superficially the "eyes and ears" of the Persian Great King; the resemblance stems from an administrative need common to both the Persian and Roman Empires and probably does not suggest institutional borrowing by the Romans from their oriental predecessors.
The evidence connecting them with the collection of taxes, especially those in kind, is less explicit. I believe that they were always basically responsible for procuring grain for military uses, a duty that increased in importance in the third century A.D., as the Empire, in an era of monetary inflation, systematized collections in kind. (31) Ultimately they were concerned as well with the regulation of the grain supply of the city of Rome; they had permanent posts at Portus, where they worked with the Prefect of the Urban Grain Supply, and along the Appian Way to the grain port of Puteoli. (32) They may also have enforced collection of taxes in coin on certain professions and of customs duties along and within imperial frontiers. (33) Such activities would have justified the epithet kollectiones - "revenuers" - applied to them and to their associates by Greek-speaking provincials of the early third century. (34) Accordingly, their activity as internal security police was not their only important service in the interests of administrative centralization, even though it may be the one that immediately arrests the attention of the modern observer.
It cannot be stated categorically that their corps began serving as a secret service agency immediately upon its foundation. Certainly by the first quarter of the second century the frumentarii were spies in the service of the central government, and it is tempting to suppose that their potential use in this capacity should not long have escaped the attention of a ruthless or efficient emperor, like Domitian himself. The first emperor known to have used them as detectives was Hadrian, who put them to work spying on the imperial court. (35) Evidence which shows them acting as spies is rather extensive from the late second and early third centuries. At that time, no class, high or low, could escape their prying. Prominent generals and senators as well as lowly Christians were particular objects of attention for the frumentarii. (36) In Rome itself, they appear to have worked closely with the urban police force. (37) In addition to investigating and arresting, they were commissioned to carry out political assassinations. (38) As detectives, the unofficial epithet, curiosi - "snoops" or "busybodies" - was probably applied to them by about A.D.200. (39) The ways in which they did their sleuthing remain obscure. Romans were familiar with the use of plain-clothes men and agents provocateurs; even though no source states specifically that frumentarii were so used, one may imagine that they were, when entrusted with delicate and confidential assignments. (40) There is, however, definite evidence that in certain capacities, especially as bureaucrats and couriers, their presence was not hidden but rather revealed clearly and intentionally by the uniforms they wore and by the characteristic ensigns they carried. (41) It is interesting that imperial government occasionally advertised the presence of these representatives of authority and centralization in order to remind its subjects forcibly that they owed its agents the respect due the majesty of Rome itself.
In addition to their main duties, many miscellaneous activities were assigned to the frumentarii, some of which had little or no bearing on internal security. They were occasionally supervisors of public mines and quarries, (42) of prisons, (43) of public works, (44) and, apparently, of mimic spectacles presented on Roman and perhaps provincial stages. (45) Like their successors in the Late Empire, they could be called upon to perform any important task the central government chose to assign them.
Individually, the duties of the frumentarii did not differ markedly from those of certain other military bureaucrats of non-commissioned grades who might also have been called upon occasionally to act as spies, policemen, tax collectors, couriers, building supervisors, etc... (46) In the aggregate, however, the functions of the frumentarii represented something unique and essential and thus set their corps apart from others affiliated with either the provincial or general staffs.
The sources give very little information regarding the character of these agents of the central administration and the attitude of Rome's subjects to them. Inscriptions often testify to their human qualities as loyal friends and as devoted husbands, fathers, and sons. Nevertheless, their duties were not such as to endear them to the population at large. At the lowest echelons of governement, Roman imperial administrators even in the most enlightened periods could be arbitrary, authoritarian, and corrupt, especially where the collection of imperial revenues and the detection of subversion were concerned. Even had the frumentarii all been dedicated and incorruptible men, they were bound to be disliked.
The tempation to exceed their authority was probably great. By the third century at the latest, when they were under increasing pressure from higher echelons to guarantee the flow of revenue in kind and to protect the security of an increasingly impoverished and apparently disintegrating state, they were roundly hated by Rome's subjects. During the Severan dynasty, paeasants in Asia Minor complained bitterly regarding arbitrary arrests and exactions made by these men and their associates. (47) An inscription from the province of Asia honors a centurio frumentarius, who, although he had the opportunity, did not oppress the provincials. (48) We have it on fairly good authority that they were regarded as a plague by the last quarter of the third century. (49) Their snooping had become unbearable, and their general conduct, at least in fiscal matters, resembled that of a plungering army. Commentators during the Late Empire were unanimous in comparing the frumentarii with their successors, the agentes in rebus, (50) who are generally reputed to have been the corrupt minions of a police state. The Roman secret service had to perform tasks both necessary and unpopular; this should not obscure the fact that they represented a rule of law which, in application, was at best often impersonal or arbitrary and at worst inhumane.
The secret service remained an essential institution of government during the Late Empire. It appears that Diocleatian, who is generally credited with "disbanding" the frumentarii, rather reorganized them on a quasi-military basis with a new name, "general agents" - agentes in rebus. (51) This corps performed a wide range of functions almost identical to those of its predecessor. It differed from the frumentarii, however, in several ways. Its recruitment was civilian rather than military, even though the titles of rank applied to the corps, as well as its privileges, were those of field soldiers. Its relation to the central administration was changed in two important ways. The general agents were removed from the jurisdiction of the praetorian prefecture and were placed under a new official of ministerial rank functioning at court, the Master of the Offices. (52) Their activities and careers were coordinated with those of the secretaries serving the imperial Privy Council or Consistory, who formed an important second branch of the internal security organization. (53) The general agents were much more numerous than the frumentarii had been, and their corps included on occasion about twelve hundred men. (54)
Of special interest is the relation of these general agents to certain ministries of state, like the praetorian and urban prefectures. The central goverment of the declining Empire wished the influence of its internal security organization to be pervasive, and thus seconded from the imperial court experienced spies to serve as chiefs of staff in the first echelons of administration and to control superiors and subordinates alike, somewhat in the manner of Soviet Political Commissars. (55) It appears that these agents often co-operated with rather than spied on their superiors, since the latter could patronize them in their careers. However corrupt they may have been, they survived in the government of Ostrogothic Italy in the sixth century, (56) while in the Byzantine Empire they continued to function until the central administration was again reorganized shortly after A.D. 700. (57)
To sum up: the internal security agencies of the Roman Empire deserve the title "secret service" even though their activities included many not necessarily secret or even directly related to the political safety of the state. They were primarly centralizers of administration and as such formed an integral part of early imperial bureaucracy rooted in the military establishment. They represented imperial power in spheres that could affect adversely the lives of Rome's subjects, and eventually they earned the hatred of the Empire. Although reorganized about A.D. 300, the secret service continued to perform its functions in the traditional manner. The fact that this agency lasted for six hundred years illustrates how essential it seemed to the central administration and provides a striking instance of institutional longevity for which imperial government was noted in other fields as well.