The Code was a digest of the whole mass of Roman law literature, compiled and annotated at the command of Justinian, under the supervision of the great lawyer Tribonian, who, with his helpers, reduced the chaotic mass to a logical system containing the essence of Roman law.  The first part of the Codex Constitutionem, prepared in less than a year, was published in April, 529.  The second part, the Digest or Pandects, appeared in December, 533.  To insure conformity, both were revised and issued in November, 534, the Institutiones, an elementary text-book, founded on the Institutiones of Gaius, who lived A.D. 110-180, being added, and the whole, as a complete body of law, given to the law schools at Constantinople, Rome, Alexandria, Berytus, and Caesarea, for use in their graduate course.  Later the Novellae Constitutione, or Novels, most of them in Greek, comprising statutes of Justinian arranged chronologically, completed the Code.

Forgotten or ignored during the lawless days of the Dark Ages, an entire copy of this famous code was discovered when Amalphi was taken by the Pisans in 1137.  Its publication immediately attracted the attention of the learned world.  Gratian, a monk of Bologna, compiled a digest of the canon law on the model of that work, and soon afterward, incorporating with his writings the collections of prior authors, gave his “decretum” to the public in 1151.  From that time the two codes, the civil and canon laws, were deemed the principal repositories of legal knowledge, and the study of each was considered necessary to throw light on the other.

Justinian’s example in the codification of laws was followed by almost every European nation after the eighteenth century; the Code Napoleon (1803-04), regulating all that pertains “to the civil rights of citizens and of property,” being the most brilliant parallel to the Justinian Code.  The reader familiar with the life of Napoleon will recall that all of his historians quote his frequent allusion to the Code Napoleon as the one great work which would be a living monument of his career, when the glory of all his other achievements would be dimmed by time or forgotten.

Gibbon’s examination of the Justinian Code is justly regarded as one of the most important features of the historian’s great work, and in several of the leading universities of Europe has long been used as a text-work on civil law.

When Justinian ascended the throne, the reformation of the Roman jurisprudence was an arduous but indispensable task.  In the space of ten centuries, the infinite variety of laws and legal opinions had filled many thousand volumes, which no fortune could purchase and no capacity could digest.  Books could not easily be found; and the judges, poor in the midst of riches, were reduced to the exercise of their illiterate discretion.