Constitutio Antoniniana

One enactment, sixteen surviving lines

Caracalla issued an enactment — probably an edict — granting Roman citizenship to all or almost all free inhabitants of the empire who did not already hold it. It is traditionally dated 212, though the Oxford Classical Dictionary allows 212 or early 213, and no promulgation day is secure.

What survives is a damaged Greek text on Papyrus Gissensis 40: sixteen lines in its battered left column. Even its identification as the edict has generated scholarly controversy.

Thanks to the gods, or a tax bill

The papyrus presents the grant as an act of gratitude to the gods, and appears to except a group called dediticii whose identity remains disputed.

Cassius Dio, a hostile contemporary, instead attributed the grant to Caracalla's wish to enlarge revenue from taxes that noncitizens had not paid. The jurist Ulpian, in a passage preserved as Digest 1.5.17, simply states that those in the Roman world were made citizens by the constitution of Emperor Antoninus.

What it did not do

Recipients acquired Roman citizenship in addition to their existing local civic identities. The enactment did not abolish local laws, privileges or community obligations.

Nor did it enfranchise a wholly excluded population: Myles Lavan's high-uncertainty model estimates that as many as a third of free provincials may already have been citizens.

Epigraphic evidence soon shows many of the new citizens using the imperial nomen Aurelius.