In ancient Rome, a promagistrate (Latin: pro magistratu) was a person who was granted the power via prorogation to act in place of an ordinary magistrate in the field.
[2] Sometimes men who held no elected public office – that is, private citizens (privati) – were given imperium and prorogued, as justified by perceived military emergencies.
The senate ordered Philo, whose consulship was about to expire, to continue to perform his military duties as he was on the verge of capturing Palaepolis (modern day Naples) and completing his provincia (assigned task).
[18] Livy reports that legislation was then moved by the tribunes that "when [Quintus Publilius' term expired] he should continue to manage the campaign pro consule until he should bring the war with the Greeks to an end".
[1] During the Second and Third Samnite Wars (326–290 BC), prorogation became a regular administrative practice that allowed continuity of military command without violating the principle of annual magistracies, or increasing the number of magistrates who held imperium.
Territorial expansion and increasing militarization drove a recognition that the "emergencies" had become a continual state of affairs, and a regular system of allotting commands developed.
[22][23] In this early period, prorogued assignments, like the dictatorship, originated as special military commands, they may at first have been limited in practice to about six months, or the length of the campaigning season.
The legal authority for this emerged directly from the sovereign powers of the Roman assemblies who were then able "to select any man[,] whether or not he had ever been elected to office[,] and make him the commander of any provincia they wished".
The first instance may have been in 215 BC after the losses at Trebia, Trasimene, and Cannae when Marcus Claudius Marcellus was elected suffect consul in the place of Lucius Postumius Albinus, deceased.
[27] However, he was forced to resign when the augurs detected flaws in his election; even so, the people passed laws to invest him with imperium and assigned him to take a consular army regardless.
[29] Generally, prorogation became almost the norm for the provinciae of Sicily, Sardinia, Hispania, and the naval fleets due to the lack of sufficient annual magistrates.
[31][32] The close of the wartime crisis and the return of annual governors also dampened the length of prorogations, allowing the senate to regain more granular control over provincial assignments.
[33] At the beginning, there were two distinct forms of prorogation – per T. Corey Brennan's Praetorship in the Roman republic – a prorogatio before the people to determine whether a provincial command should be extended and a propagatio from the senate in other cases.
[34] But by the 190s BC, the senate stopped submitting decisions on prorogation of permanent provinciae to the people for ratification and eventually all extensions of imperium were called prorogatio.
[38] The addition of the wealthy Asian province in 133 BC as a bequest of Attalus III put further pressure on the system, again without increasing the number of praetorships: The senate evidently placed a premium on controlling competition for the consulship, and chose to neglect the rapidly accelerating erosion of a fundamental Republican constitutional principle — the annual magistracy — as well as to ignore the added inconvenience to commanders and possible danger to provincials...
[10][40] The scale of Roman military commitments in annexed territories during the late republic required regular prorogation, since the number of magistrates and ex-magistrates who were both able commanders and willing to accept provincial governorships did not increase proportionally.
When Sulla assumed the dictatorship in late 82 BC, the territorial provinces alone numbered ten, with possibly six permanent courts to be presided over in the city.
[41] The rise of popularis political tactics from the time of Gaius Marius forward also coincided with the creation of "super provinciae", "massive commands in which multiple permanent provinces were incorporated into a single consular provincial assignment" with "proportionately larger military and financial resources".
[47] One of the few exceptions to this rule was a senatorial snub against Octavian in 43 BC when he was vested with imperium and prorogued pro praetore, putting him lower in status than all other promagistrates.