The Liber Augustalis or Constitutions of Melfi Promulgated by the Emperor Frederick II for the Kingdom of Sicily in 1231

The Liber Augustalis was born of no grand design but of the demands of government. This body of law marked a moment of triumph in the long and frustrating struggle by which Frederick attempted to establish his royal authority in the Kingdom of Sicily. Frederick had smashed rebellions by the Muslim population and by the nobility, while he systematically negotiated with the clergy over disputed domains. It was as a victorious king and emperor that he ordered the compilation of the Liber Augustalis-a cornerstone of royal authority-in part a summing up of the previous legal efforts of the monarchy, in part a significant move beyond the limitations of previous legislation.
The Liber Augusta/is blended many disparate influences into a common body of law. The existing legal traditions-Lombard, Byzantine, and Norman-the Canon law of the Church, and the learning of the Bolognese scholars, especially Master Petrus Della Vigna, provided sources on which Frederick could draw, but the laws represent the viewpoint of the monarchy rather than those of the powerful groups within the kingdom-Church, nobility, and towns whose interests were often counter to those of the king. Ultimately events proved that the greatest danger to Frederick's rule lay not in the kingdom itself but in the determination of the papacy and the Roman curia to prevent Sicily from becoming the seat of empire in Italy. In 1231, however, when Frederick was formulating his imperial policy, the first priority lay in establishing the strongest posture for monarchy.