Constitutio Antoniniana

The Constitutio Antoniniana (Latin for: "Constitution [or Edict] of Antoninus") (also called the Edict of Caracalla or the Antonine Constitution) was an edict issued in 212, by the Roman Emperor Caracalla declaring that all free men in the Roman Empire were to be given theoretical Roman citizenship and that all free women in the Empire were to be given the same rights as Roman women.

Before 212, for the most part only inhabitants of Italy held full Roman citizenship. Colonies of Romans established in other provinces, Romans (or their descendants) living in provinces, the inhabitants of various cities throughout the Empire, and small numbers of local nobles (such as kings of client countries) held full citizenship also. Provincials, on the other hand, were usually non-citizens, although some held the Latin Right.

The Roman jurist Ulpian's Digest stated, "All persons throughout the Roman world were made Roman citizens by an edict of the Emperor Antoninus Caracas" (D. 1.5.17).

The context of the decree is still subject to discussion. According to Cassius Dio, the main reason Caracalla passed the law was to increase the number of people available to tax. In the words of Cassius Dio: "This was the reason why he made all the people in his empire Roman citizens; nominally he was honoring them, but his real purpose was to increase his revenues by this means, inasmuch as aliens did not have to pay most of these taxes." It should, however, be noted that Cassius Dio generally saw Caracalla as a bad, contemptible emperor.

Another goal may have been to increase the number of men able to serve in the legions, as only full citizens could serve as legionaries in the Roman Army. In scholarly interpretations that followed a model of moral degeneration as the reason for the fall of the Roman Empire, notably the model followed by Edward Gibbon, the edict came at the cost to the auxiliaries, which primarily consisted of non-citizen men, and led to barbarization of the Roman military.

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