PRAGMATIC SANCTION. — I. The term "pragmatic sanction" is applied in the late Roman Empire to a type of imperial constitution whose nature is controversial and not reducible to a single concept. Sometimes the p. s. contains provisions of a general character, at other times specific norms; it is commonly considered to be something intermediate between a *lex generalis* and a *rescriptum*; recently, it has been likened to an emergency ordinance.
In some cases, it serves to transmit legislative documents, such as the p. s. which, according to the provisions of Theodosius II, was to accompany constitutions issued by the emperor of one of the imperial divisions so that those constitutions would have force in the territory subject to the authority of a colleague. A famous p. s. is the one known as the *pro petitione Vigilii* of 14 August 554, by which Justinian sent to the West, at the request of Pope Vigilius, a collection of his constitutions and confirmed the validity of the parts of his codification previously promulgated in Italy.
