legionary base (Xanten, Germany), believed to have belonged to the classical author
Pliny the Elder when he was a
praefectus alae (commander of an
auxiliary cavalry regiment) in
Germania Inferior (source:
British Museum, London).
Differentiation of the senatorial order The Senate as a body was formed of sitting senators, whose number was held at around 600 by the founder of the Principate, Augustus (sole rule 30 BC – 14 AD) and his successors until 312. Senators' sons and further descendants technically retained equestrian rank unless and until they won a seat in the Senate. But Talbert argues that Augustus established the existing senatorial elite as a separate and superior order (
ordo senatorius) to the
equites for the first time. The evidence for this includes: • Augustus, for the first time, set a minimum property requirement for admission to the Senate, of 250,000
denarii, two and a half times the 100,000
denarii that he set for admission to the equestrian order. • Augustus, for the first time, allowed the sons of senators to wear the
tunica laticlavia (tunic with broad purple stripes that was the official dress of senators) on reaching their majority even though they were not yet members of the Senate. • Senators' sons followed a separate
cursus honorum (career-path) to other
equites before entering the Senate: first an appointment as one of the
vigintiviri ("Committee of Twenty", a body that included officials with a variety of minor administrative functions), or as an
augur (priest), followed by at least a year in the military as
tribunus militum laticlavius (deputy commander) of a legion. This post was normally held before the tribune had become a member of the Senate. • A marriage law of 18 BC (the
lex Julia) seems to define not only senators but also their descendants unto the third generation (in the male line) as a distinct group. There was thus established a group of men with senatorial rank (
senatorii) wider than just sitting senators (
senatores). A family's senatorial status depended not only on continuing to match the higher wealth qualification, but on their leading member holding a seat in the Senate. Failing either condition, the family would revert to ordinary knightly status. Although sons of sitting senators frequently won seats in the Senate, this was by no means guaranteed, as candidates often outnumbered the 20 seats available each year, leading to intense competition.
Ordo equester under Augustus As regards the equestrian order, Augustus apparently abolished the rank of
equo privato, according all its members
equo publico status. In addition, Augustus organised the order in a quasi-military fashion, with members enrolled into six
turmae (notional cavalry squadrons). The order's governing body were the
seviri ("Committee of Six"), composed of the "commanders" of the
turmae. In an attempt to foster an
esprit de corps amongst the
equites, Augustus revived a defunct republican ceremony, the
recognitio equitum (inspection of the
equites), in which
equites paraded every five years with their horses before the consuls. At some stage during the early Principate,
equites acquired the right to the title "egregius" ("distinguished gentleman"), while senators were styled "
clarissimus" ("most distinguished"). Beyond
equites with
equus publicus, Augustus' legislation permitted any Roman citizen who was assessed in an official census as meeting the property requirement of 100,000
denarii to use the title of
eques and wear the narrow-striped tunic and gold ring. But such "property-qualified
equites" were not apparently admitted to the
ordo equester itself, but simply enjoyed equestrian status. Only those granted an
equus publicus by the emperor (or who inherited the status from their fathers) were enrolled in the order. Imperial
equites were thus divided into two tiers: a few thousand mainly Italian
equites equo publico, members of the order eligible to hold the public offices reserved for the
equites; and a much larger group of wealthy Italians and provincials (estimated at 25,000 in the 2nd century) of equestrian status but outside the order. Equestrians could in turn be elevated to senatorial rank (e.g.,
Pliny the Younger), but in practice this was much more difficult than elevation from commoner to equestrian rank. To join the upper order, not only was the candidate required to meet the minimum property requirement of 250,000
denarii, but also had to be elected a member of the Senate. There were two routes for this, both controlled by the emperor: • The normal route was election to the post of
quaestor, the most junior magistracy (for which the minimum eligible age was 27 years), which carried automatic membership of the Senate. Twenty
quaestors were appointed each year, a number that evidently broadly matched the average annual vacancies (caused by death or expulsion for misdemeanours or insufficient wealth) so that the 600-member limit was preserved. Under Augustus, senators' sons had the right to stand for election, while equestrians could only do so with the emperor's permission. Later in the Julio-Claudian period, the rule became established that all candidates required imperial leave. Previously conducted by the people's assembly (
comitia centuriata), the election was in the hands, from the time of
Tiberius onwards, of the Senate itself, whose sitting members inevitably favoured the sons of their colleagues. Since the latter alone often outnumbered the number of available places, equestrian candidates stood little chance unless they enjoyed the special support of the emperor. • The exceptional route was direct appointment to a Senate seat by the emperor (
adlectio), technically using the powers of
Roman censor (which also entitled him to expel members).
Adlectio was, however, generally used sparingly in order not to breach the 600-member ceiling. It was chiefly resorted to in periods when Senate numbers became severely depleted, e.g. during the
Civil War of 68–69, following which the emperor
Vespasian made large-scale
adlectiones.
Equestrian public careers period (193–211). Equestrians exclusively provided the
praefecti (commanders) of the imperial army's
auxiliary regiments and five of the six
tribuni militum (senior staff officers) in each legion. The standard equestrian officer progression was known as the "
tres militiae" ("three services"):
praefectus of a
cohors (auxiliary infantry regiment), followed by
tribunus militum in a legion, and finally
praefectus of an
ala (auxiliary cavalry regiment). From the time of Hadrian, a fourth militia was added for exceptionally gifted officers, commander of an
ala milliaria (double-strength
ala). Each post was held for three to four years. Most of the top posts in the imperial administration were reserved for senators, who provided the governors of the larger provinces (except Egypt), the
legati legionis (legion commanders) of all legions outside Egypt, and the
praefectus urbi (prefect of the city of Rome), who controlled the
cohortes urbanae (public order battalions), the only fully armed force in the city apart from the Praetorian Guard. Nevertheless, a wide range of senior administrative and military posts were created and reserved for equestrians by Augustus, though most ranked below the senatorial posts. In the imperial administration, equestrian posts included that of the governorship (
praefectus Augusti) of the
province of Egypt, which was considered the most prestigious of all the posts open to
equites, often the culmination of a long and distinguished career serving the state. In addition,
equites were appointed to the governorship (
procurator Augusti) of some smaller provinces and sub-provinces e.g.
Judaea, whose governor was subordinate to the governor of
Syria. Equestrians were also the chief financial officers (also called
procuratores Augusti) of the imperial provinces, and the deputy financial officers of senatorial provinces. At Rome, equestrians filled numerous senior administrative posts such as the emperor's secretaries of state (from the time of Claudius, e.g. correspondence and treasury) and the
praefecti annonae (director of grain supplies). In the military, equestrians provided the
praefecti praetorio (commanders of the Praetorian Guard) who also acted as the emperor's chiefs of military staff. There were normally two of these, but at times irregular appointments resulted in just a single incumbent or even three at the same time. Equestrians also provided the
praefecti classis (admirals commanding) of the two main imperial fleets at
Misenum in the bay of Naples and at
Ravenna on the Italian
Adriatic coast. The command of Rome's fire brigade and minor constabulary, the
vigiles, was likewise reserved for
equites. Not all
equites followed the conventional career-path. Those equestrians who specialised in a legal or administrative career, providing judges (
iudices) in Rome's law courts and state secretaries in the imperial government, were granted dispensation from military service by Emperor
Hadrian (r. AD 117–138). At the same time, many
equites became career military officers, remaining in the army for much longer than 10 years. After completing their
tres militiae, some would continue to command auxiliary regiments, moving across units and provinces. Already wealthy to start with,
equites equo publico accumulated even greater riches through holding their reserved senior posts in the administration, which carried enormous salaries (although they were generally smaller than senatorial salaries). For example, the salaries of equestrian
procuratores (fiscal and gubernatorial) ranged from 15,000 to a maximum of 75,000
denarii (for the governor of Egypt) per annum, whilst an equestrian
praefectus of an auxiliary cohort was paid about 50 times as much as a common foot soldier (about 10,000
denarii). A
praefectus could thus earn in one year the same as two of his auxiliary rankers combined earned during their entire 25-year service terms.
Relations with the emperor It was suggested by ancient writers, and accepted by many modern historians, that Roman emperors trusted equestrians more than men of senatorial rank, and used the former as a political counterweight to the senators. According to this view, senators were often regarded as potentially less loyal and honest by the emperor, as they could become powerful enough, through the command of provincial legions, to launch
coups. They also had greater opportunities for
peculation as provincial governors. Hence the appointment of equestrians to the most sensitive military commands. In Egypt, which supplied much of Italy's grain needs, the governor and the commanders of both provincial legions were drawn from the equestrian order, since placing a senator in a position to starve Italy was considered too risky. The commanders of the Praetorian Guard, the principal military force close to the emperor at Rome, were also usually drawn from the equestrian order. Also cited in support of this view is the appointment of equestrian fiscal
procuratores, reporting direct to the emperor, alongside senatorial provincial governors. These would supervise the collection of taxes and act as watchdogs to limit opportunities for corruption by the governors (as well as managing the imperial estates in the province). According to Talbert, however, the evidence suggests that
equites were no more loyal or less corrupt than senators. For example, c. 26 BC, the equestrian governor of Egypt,
Cornelius Gallus, was recalled for politically suspect behaviour and sundry other misdemeanours. His conduct was deemed sufficiently serious by the Senate to warrant the maximum penalty of exile and confiscation of assets. Under Tiberius, both the senatorial governor and the equestrian fiscal procurator of
Asia province were convicted of corruption. There is evidence that emperors were as wary of powerful
equites as they were of senators. Augustus enforced a tacit rule that senators and prominent equestrians must obtain his express permission to enter the province of Egypt, a policy that was continued by his successors. Also, the command of the Praetorian Guard was normally split between two
equites, to reduce the potential for a successful ''coup d'état
. At the same time, command of the second military force in Rome, the cohortes urbanae'', was entrusted to a senator.
Oligarchical rule in the early Principate (to 197 AD) Because the Senate was limited to 600 members,
equites equo publico, numbering several thousands, greatly outnumbered men of senatorial rank. Even so, senators and
equites combined constituted a tiny elite in a citizen-body of about 6 million (in 47 AD) and an empire with a total population of 60–70 million. This immensely wealthy elite monopolised political, military and economic power in the empire. It controlled the major offices of state, command of all military units, ownership of a significant proportion of the empire's arable land (e.g., under
Nero (), half of all land in
Africa Proconsularis province was owned by just six senators) and of most major commercial enterprises. Overall, senators and
equites cooperated smoothly in the running of the empire. In contrast to the chaotic civil wars of the late Republic, the rule of this tiny oligarchy achieved a remarkable degree of political stability. In the first 250 years of the Principate (30 BC – 218 AD), there was only a single episode of major internal strife: the
civil war of 68–69.
Equestrian hierarchy It seems that from the start the equestrians in the imperial service were organised on a hierarchical basis reflecting their pay-grades. According to
Suetonius, writing in the early part of the second century AD, the equestrian procurators who "performed various administrative duties throughout the empire" were from the time of
Emperor Claudius I organised into four pay-grades, the
trecenarii the
ducenarii, the
centenarii, and the
sexagenarii, receiving 300,000, 200,000, 100,000, and 60,000 sesterces per annum respectively. Cassius Dio, writing a century later, attributed the beginnings of this process to the first emperor, Augustus, himself. There is almost no literary or epigraphic evidence for the use of these ranks until towards the end of the 2nd century. However, it would seem that the increasing employment of equestrians by the emperors in civil and military roles had had social ramifications for it is then that there begin to appear the first references to a more far-reaching hierarchy with three distinct classes covering the whole of the order: the
Viri Egregii (Select Men); the
Viri Perfectissimi ("Best of Men"); and the
Viri Eminentissimi ("Most Eminent of Men"). The mechanisms by which the equestrians were organised into these classes and the distinctions enforced is not known. However, it is generally assumed that the highest class, the
Viri Eminentissimi, was confined to the
Praetorian prefects, while the
Viri Perfectissimi were the heads of the main departments of state, and the great prefectures, including Egypt, the city watch (
vigiles), the corn supply (
annona) etc. and men commissioned to carry out specific tasks by the emperor himself such as the military
duces. The defining characteristic of the
perfectissimate seems to have been that its members were of or associated socially (i.e. as
clientes - see
Patronage in ancient Rome of Great Men) with the imperial court circle and were office-holders known to the emperor and appointed by his favour. It is also possible that system was intended to indicate the hierarchy of office-holders in situations where this might be disputed. The
Viri Egregii comprehended the rest of the Equestrian Order, in the service of the emperors. The
Viri Egregii included officials of all four pay-grades.
Ducenariate procurators governing provinces not reserved for senators were of this category, as were the
praefecti legionum, after
Gallienus opened all legionary commands to equestrians. However, it seems that after 270 AD the
procuratores ducenarii were elevated into the ranks of the
Viri Perfectissimi. ==Equestrians in the later Empire (AD 197–395)==