the first official collection of ordinances of the Roman emperors; it was compiled in 435 by a commission of 16 jurists appointed by Theodosius II, the emperor of the Eastern Roman Empire, and was published Feb. 15, 438. The edition was preceded by private codifications that had no official significance: the Codex Gregorianus, which contained ordinances (constitutions) of emperors who reigned from 196 to 295, and the Codex Hermogenianus, which contained later constitutions. Both codices are known only in excerpts. The Codex Theodosianus consisted of 16 books divided into chapters (titles), including all constitutions that were in force from 313 to 437. According to Theodosius, the codex was to include the Gregorianus and Hermogenianus codices, which were thus officially sanctioned. The Codex Theodosianus was adopted by the coruler of Theodosius, Valentinian III, and thus also became binding in the Western Roman Empire.
The Codex Theodosianus reflected changes that had occurred in the state and social life of the Roman Empire, particularly its feudalization.