PRAEFECT (praefectus), the title of various Roman officials, both civil and military. A praefect was not one of the magistrates proper; he was, strictly speaking, only the deputy or lieutenant of a superior magistrate or commander. The following were the most important.
1. The city praefect (praefectus urbis) acted at Rome as the deputy of the chief magistrate or magistrates during his or their absence from the city. Thus he represented in the earliest times the king and in later times the consul or consuls when he or they were absent on a campaign or on other public duties, such as the celebration of the annual Latin festival on the Alban Mount. The absence of the chief magistrate for more than a single day rendered the appointment of a praefect obligatory; but the obligation only arose when all the higher magistrates were absent. Hence so long as the consuls were the only higher magistrates their frequent absence often rendered the appointment of a praefect necessary, but after the institution of the praetor ship (367 B.C.) the necessity only arose exceptionally, as it rarely happened that both the consuls and the praetor were absent simultaneously. But a praefect continued to be regularly appointed, even under the empire, during praefedus the enforced absence of all the higher magistrates Ui-bis at the Latin festival. The right and duty of appoint- Fefilmm ing a praefect belonged to the magistrate (king, dictator or consul) whose deputy he was, but it seems to have been withdrawn from the consuls by the Licinian law (367), except that they still nominated prefects for the time of the festival. No formalities in the appointment and no legal qualifications on the part of the praefect were required. The praefect had all the powers of the magistrate whose deputy he was, except that he could not nominate a deputy to himself. His office expired on the return of his superior. There could only be one city praefect at a time, though the dictator Caesar broke the rule by appointing six or eight prefects simultaneously.
Under the empire there was introduced a city prefecture which differed essentially from the above. Augustus occasionally appointed a city praefect to represent him in his absence from Italy, although the praetors, or even one of the consuls, remained in the capital. In the absence of Tiberius from Rome during the last eleven years of his reign (A.D. 26–37) the city prefecture, hitherto an exceptional and temporary office, became a regular and permanent magistracy; in all subsequent reigns the praefect held office even during the presence of the emperor in Rome. He was always chosen by the emperor and usually from men who had held the consulship; his office was regarded, like the censorship under the republic, as the crowning honour of a long political career. It was not conferred for any definite length of time, but might be held for years or for life. As under the republic, the praefect was not allowed to quit the city for more than a day at a time. His duty was the preservation of peace in the capital; he was, in fact, the chief of the police, being charged with the superintendence of the streets, markets and public buildings. He was further entrusted by Augustus with a summary criminal jurisdiction over slaves and rioters, which was, however, gradually extended till in the time of Severus or even earlier it embraced all offences by whomsoever committed. Further, he had the power of dealing with civil cases where his interference seemed requisite in the interests of the public safety, but such occasions were naturally few. By the beginning of the 3rd century, and perhaps earlier, appeals to the emperor in civil cases were handed over by him to be dealt with by the praefect. Except where special restrictions interfered, an appeal lay from the praefect to the emperor. Though not a military officer, the praefect commanded the city cohorts (cohortes urbanae), which formed part of the garrison of Rome and ranked above the line regiments, though below the guards (see Praetorians). The military power thus placed in the hands of the chief of the police was one of the most sorely-felt innovations of the empire. The constitutional changes of Diocletian and Constantine extended still further the power of the praefect, in whom, after the disbanding of the guards and the removal from Rome of the highest officials, the whole military, administrative and judicial powers were centred.
2. Under the republic judicial prefects (praefecti jure dicendo) were sent annually from Rome as deputies of the praetors to administer justice in certain towns of the Italian allies. These towns'were called prefectures (praefecturae). After the Social War (90-89 B.c.), when. all Italy had received the Roman franchise, such prefectures ceased to exist in fact, though the name was sometimes retained.
3. Under the empire the praetorian or imperial guards were commanded by one, two, or even three prefects (praefecti praetorio), who were chosen by the emperor from among the knights and held office at his pleasure. From the time of Alexander Severus the post was open to senators also, and if a knight was appointed he was at the same time raised to the senate. Down to the time of Constantine, who deprived the office of its military character, the prefecture of the guards was regularly held by tried soldiers, often by men who had fought their way up from the ranks. In course of time the command seems to have been enlarged so as to include all the troops in Italy except the corps commanded by the city praefect (cohortes urbanae). Further, the praetorian praefect acquired, in addition to his military functions, a criminal jurisdiction, which he exercised not as the delegate but as the representative of the emperor, and hence it was decreed by Constantine (331) that from the sentence of the praetorianpraefect there should be no appeal. A similar jurisdiction in civil cases was acquired by him not later than the time of Severus. Hence a knowledge of law became a qualification for the post, which under Marcus Antoninus and Commodus, but especially from the time of Severus, was held by the first jurists of the age, (e.g. Papinian, Ulpian and Paullus), While the military qualification fell more and more into the background. Under Constantine the institution of the magistri militum deprived the praetorian prefecture altogether of its military character; but left it the highest civil office of the empire.
The title of “praefect” was borne by various other Roman officials, of whom we may mention the following:—
4. Praefectus Socium (sociorum).-Under the republic the contingents furnished to the Roman armies by the Italian allies were commanded by Roman officers called praefecti socium (sociorum), who were nominated by the consuls and corresponded to the tribunes in the legions.
5. Praefectus Classium.—Down to near the close of the republic a naval command was never held independently but only in Connexion with the command of an army, and, when the general appointed an officer to command the fleet in his room, this lieutenant was styled “praefect of the fleet” (praefectus classium). When in 311 B.C. the people took the appointment of these lieutenants into their own hands the title was changed from “praefects” to duo viri navales, or “two naval men”; but under the empire the admirals went by their old name of prefects.
6. Praefectus Fabrum.—The colonel of the engineer and artillery corps (fabri) in a Roman army was called a praefect; he did not belong to the legion, but was directly subordinate to the general in command.
7. Praefectus Annonae.—The important duty of provisioning Rome was committed by Augustus (between A.D. 8 and 14) to a praefect, who was appointed by the emperor from among the knights and held office at the imperial pleasure.
8. Praefectus Aegypti (afterwards Prczefectus augustalis).-Under the empire the government of Egypt was entrusted to a Viceroy with the title of “praefect,” who was selected from the knights, and was surrounded by royal pomp instead of the usual insignia of a Roman magistrate. He stood under the immediate orders of the emperor. The exceptional position thus accorded to Egypt was due to a regard on the part o the emperors to the peculiar character of the population, the strategic strength of the country, and its political importance as the granary of Rome. (J. G. Fr.)
9. Praefectus Castrorum, from the time of Augustus to Severus the title of the commander of the fixed camps of the legions in different parts of the empire. He was a purely military man appointed by the emperor, usually a centurion whose term of service was completed. From the time of Domitian, when each legion had a separate Camp, the name of the legion was added to the title, e.g. praefectus castrorum legionis xiii. gem. (C.I.L. iii. 454). The duties of this officer included: the arrangement of the camp and medical service, the transport of the baggage, the construction of roads, bridges and fortifications, the supply of ammunition and engines of war.
10. Praefectus Vigilum, the commander of the seven cohortes vigilum, a night police force instituted by Augustus (A.D. 6). To each cohort, consisting of about 1000 men (chiefly freedmen), was entrusted the care of two of the fourteen city districts; one of its chief duties was that of a fire brigade. The policing of the city had formerly been one of the' duties of the aediles, but was now transferred to the praefectus vigilum, appointed by the emperor from the equites. He exercised criminal jurisdiction in cases of incendiarism and offences committed against the law during the night, and in later times this jurisdiction was considerably extended.
The different kinds of prefects are fully discussed in Mommsen, Römisches Staatsrecht (1887) vols. ii., iii.; see also T. M. Taylor, Constitutional and Political History of Rome (1899). There is an excellent monograph on the Praefectura urbis by P. E. Vigneaux (1896). Mommsen deals very cursorily with the praefectus castrorum, but there is a special article by G. Wilmanns, in Ephemeris epigraphical (1872), vol. i., “De praefecto castrorum et praefecto legionis.”
For the French préfet see Prefect. (X.)