praetorian prefect

Roman official

Also known as: praefectus praetorio

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July 13, 2026

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The praetorian prefect was a high-ranking official in ancient Rome, initially appointed by the consuls to act in their absence. The position evolved significantly, with Emperor Augustus establishing two praetorian prefects to command the Praetorian Guard, the emperor's personal bodyguards.12

This role rapidly gained immense power, as the prefect was responsible for the emperor's safety. Some praetorian prefects became de facto prime ministers, and a few even seized the throne themselves. By the later empire, they managed vast civil administration, including judicial powers, tax collection, and troop command. Emperor Constantine I eventually stripped them of military duties, but they retained significant judicial and financial responsibilities until the empire's end. The Praetorian Guard itself was disbanded by Constantine in 312 AD.123

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prefect
…prefect of the city, two praetorian prefects (praefectus praetorio), a prefect of the fire brigade, and a prefect of the grain supply. The prefect of the city was responsible for maintaining law and order within Rome and acquired full criminal jurisdiction in the region within 100 miles (160 km) of…
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…prefect of the city, two praetorian prefects (praefectus praetorio), a prefect of the fire brigade, and a prefect of the grain supply. The prefect of the city was responsible for maintaining law and order within Rome and acquired full criminal jurisdiction in the region within 100 miles (160 km) of…
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Constantine I
Legacy of Constantine I
…was the emergence of regional praetorian prefectures with supreme authority over civil financial administration but with no direct control over military affairs; this they yielded to new magistri, or “masters,” of the cavalry and infantry forces. The reduction of the prefects’ powers was seen by some as excessively innovatory, but…
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…was the emergence of regional praetorian prefectures with supreme authority over civil financial administration but with no direct control over military affairs; this they yielded to new magistri, or “masters,” of the cavalry and infantry forces. The reduction of the prefects’ powers was seen by some as excessively innovatory, but…
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France
Gaul under the late Roman Empire (c. 250–c. 400)
…of the highest rank, a praetorian prefect, was based there, and a series of emperors and usurpers (in particular, Constantine I [reigned 306–337], Julian [355–363], Valentinian I [364–375], Gratian [375–383], and Magnus Maximus [383–388]) resided there for at least part of their reigns. Their seat of government was usually Augusta
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…of the highest rank, a praetorian prefect, was based there, and a series of emperors and usurpers (in particular, Constantine I [reigned 306–337], Julian [355–363], Valentinian I [364–375], Gratian [375–383], and Magnus Maximus [383–388]) resided there for at least part of their reigns. Their seat of government was usually Augusta
Read More