Ancient History & Civilisation

Senatorial Officers under the Principate

(Above) A relief from Holland depicting the Emperor Tiberius offering a ritual popanum cake in sacrifice

(Opposite) In this scene from Trajan's Column, the Emperor Trajan is shown in the uniform of a senior senatorial officer on campaign.

Whilst the creation of the Principate robbed the Senate of any real freedom and independence, senators as individuals continued to play a central role in the running of the Empire until well into the 3rd century, providing the overwhelming majority of provincial governors and senior army officers. A few served in offices which had long existed under the Republic, although most were in newly created posts which made explicit the fact that their authority came from the Emperor. All now operated in a completely different political environment which restricted their freedom of action. Men were no longer elected to magistracies which brought them civil and military responsibilities. A successful career depended primarily on influence and patronage and most of all required imperial approval. This was especially true for the more important military commands, for no emperor wanted to give control of legions to a man who might become a rival.

A senator’s son who aspired to a public career normally served as a junior magistrate in his late teens. Most became one of the ‘board of 20’ (vigin- tiviri) in Rome, before receiving their first military experience as a tribunus laticlavius in one of the legions. It seems to have been fairly common for men to serve in a unit stationed in a province governed by a family member or close friend. It is distinctly possible that governors were allowed to request such postings, for we certainly know that they were able to appoint men to many lesser positions. Usually a minimum of one year was spent in the post. A minority served for longer than this, and cases are known of men serving in several legions, invariably stationed in different provinces, in succession. Later, usually at 24, although some men were granted exemptions and achieved the distinction at a younger age, a man would be formally enrolled in the Senate and might gain the quaestor- ship. This involved administering the finances of a settled province and with very few exceptions did not include military responsibilities. In subsequent years a man might hold a succession of magistracies which retained only a shadow of their former importance and involved mainly ceremonial duties.

The next military post was to become a legatus legionis in command of a legion, usually achieved around the age of 30. As a legatus or ‘representative’ these officers were clearly marked out as deputies of the emperor acting on delegated authority. These commands were certainly not at the disposal of each province’s governor, and were instead direct appointments of the emperor. Some men remained in command of a legion for six to seven years, but the average tenure seems to have been nearer three. It was very rare for a man to be appointed to the legateship of more than one legion. Following this post, a man might go on to govern a settled province - one without a significant military garrison - as a propraetor, before returning to Rome to hold the consulship.

The culmination of a man’s career was usually the post of legatus Augusti proparetore in charge of one of the military provinces of the Empire. The limited number of such posts and their importance ensured that the majority of senators never achieved this high rank. On average men served about three years in such a post, but there were many exceptions. Tiberius became unpopular with the Senate because he kept governors in office for exceptionally long periods, frustrating those aspiring to this rank by reducing the number of available commands. In the 2nd century AD it was not unusual for a man to serve in a smaller military province before gaining command of one of the largest armies in Britain, Upper Pannonia or Syria. At times of crisis experienced and loyal men might be sent to take command of an area facing a rebellion or other serious problem.

(Above) An inscription from Caesarea on the coast of Judaea recording the construction of a building dedicated to the Emperor Tiberius by f’ontius Pilate, the equestrian governor of the province Pilate’s title is given as prefect (praefectus), but by the reign of Claudius equestrian governors were blown as procurators This is the only inscription to survive from Pilate’s 10-year tenure in Judaea.

(Above) An inscription set up in honour of the legate commanding Legio II Augusta, Tiberius Claudius Paulinus, providing some details of his career. After his tenure as legionary legate, he was proconsul of one of the Gallic provinces, and then imperial legate to another. This monument probably dates to before ad 220, for in that year Paulinus became legatus Augusti of Lower Britain.

(Opposite Above) Trajan's Column formed the centrepiece to the Forum complex constructed to commemorate the Emperor’s victory in Dacia. It is 100 Roman feet high (29.8 m or 97 ft 9 in) and was originally topped by a statue of Trajan.

Only two provinces which contained a legionary garrison were not governed by imperial legates. The first, Egypt, was an equestrian command and will be dealt with in the next section. The second, Africa, was the only province administered by the Senate to contain a legion and its governor was a proconsul who possessed imperium in his own right. Although this man was chosen and appointed by the Senate, it is clear that they were expected to select someone of whom the emperor approved and under Caligula this senatorial proconsul was replaced by an imperial legate.

Competence, experience, merit and patronage

Before being placed in command of an army, a provincial legate had experience of serving as a military tribune and legionary legate. Pliny the Younger appears to have spent most of his tenure as tribune with a legion in Syria in routine administration, in particular involving a thorough inspection of unit accounts in that province. However, Pliny was never to serve with the army in any more senior capacity. Tactitus claims that his father-in-law, Agricola, was unlike most military tribunes in that he did not waste his time as tribune in debauchery, but took the post seriously and was given significant responsibilities. Much must have depended on a man’s temperament, that of his senior officers, and the local situation during his year or more of service. This is also true to a fair extent of legionary legates, although their responsibilities were significantly greater. By modern standards the generals of the Roman army were amateurs.

Some scholars have argued that from the very beginning of an aristocrat’s career his behaviour, loyalty and ability were closely scrutinized and his suitability for higher office judged. This created a group known as the viri militares or ‘military men’ who were marked out for the most important provincial commands. There is no real evidence to support this view, or any indication of just who these boards of assessors could have been. As far as we can tell, it was patronage more than anything else which dictated whether an individual’s career ended prematurely or would eventually include the highest offices. Letters of recommendation are by far the most common form of document to survive from the Roman world. The Romans did not consider this to be corruption, viewing it as both logical and proper that a man should use his authority to benefit his friends. Pliny the Younger expressed the Roman attitude in a letter written to a governor of one of the major military provinces:

‘For two reasons I have singled you out to approach with a request which I am most anxious to be granted. Your command of a large army gives you a plentiful source of benefits to confer, and secondly, your tenure has been long enough for you to have provided for your own friends. Turn to mine - they are not many.’

The emperor was the ultimate source of all patronage and, as we have seen, his favour was necessary to secure appointment as a legionary legate or provincial governor. Emperors needed capable men to command their armies and rule their provinces, but a delicate balance had to be struck for they did not wish to grant power to men who were too able and so risk creating a rival. The activities of governors were far more closely supervised than had ever been the case under the Republic. Augustus urged caution on his commanders and attempted to curb the traditionally aggressive tendencies of Roman aristocrats when placed at the head of an army. Claudius recalled the legate of Lower Germany, when the latter had begun an invasion of a German tribe to the east of the River Rhine. The legate, Gnaeus Domitius Corbulo, one of the most famous generals of the 1st century, commented on how fortunate the generals had been under the Republic, before obeying orders and returning to his province.

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