Praefectus annonae

The praefectus annonae ("Prefect of the Provisions") was a Roman imperial official charged with the supervision of the grain supply to the city of Rome. Under the republic, the job was usually done by an aedile. However, in emergencies, or in times of extraordinary scarcity, an individual would be elected to the office, and would take charge of supplying the entire city with provisions. L. Minucius Augurinus, the accuser of Spurius Maelius, was the first individual appointed to this office, serving from 439 BC. During the early 60s BC, following the sacking of the port of Ostia by pirates, Pompey held the powers of the office. Around 7 BC, the first Roman Emperor, Augustus, followed this example, and after vesting himself with these powers, specified that two former praetors should be appointed every year to carry out the functions of this office. Augustus transferred powers from the aedile to this office, and specified that all holders of this office be members of the Equestrian order. Augustus also specified that these officers were to be aided by an adjutor (from the 2nd century the subpraefectus). Later, Augustus specified that these individuals must be of consular rank. After Augustus' reign, one individual would usually hold this office, and this continued until the fall of the Roman Empire.

During the later Empire, further praefecti annonae were established for the city of Alexandria (Egypt) and the province of Africa, the two chief sources of grain for the provisioning of Rome.

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