Today marks the anniversary of the promulgation in 529 AD of the Codex of Justinian, the first part among four of the great body of Roman law now known as the “Corpus Juris Civilis – the Body of Civil Law”, promulgated from 529-34 by the Byzantine Emperor Justinian, who reigned from 527-65. However, the title “Corpus Juris Civilis” itself dates only from an edition printed at Geneva in 1583.
Since respect for the past was so deeply rooted in their whole culture and society, the Romans tended not to repeal old or obsolete laws; instead, they would either ignore them or more often, interpret them in a way that conformed with more recent laws. This inevitably led to a great deal of confusion and debate within the legal process as to which among various laws could or should be applied to a particular matter. The purpose of Justinian’s project, therefore, was to provide a definitive and universally valid body of legislation for the whole Empire.
It was entrusted to a committee headed by a jurist called Tribonian, who supervised the first three parts of the work and contributed to the fourth which was added to it later. This commission had the authority to edit and amend the earlier legal texts that they decided to keep in the compilation and remove material that was either obsolete or otherwise contradicted. As a result, the original version of many of these texts has been lost, since it was definitely supplanted by this new collection.
Tribonian Presents the Pandects to Justinian: fresco designed by Raphael, executed by his students, in the Stanza della Segnatura, now a part of the Vatican Museums. Public domain image from Wikimedia Commons, cropped.

The first part is the Codex of Justinian properly so-called, although this term is often extended to the whole body of the legal work issued by his authority. It contained the Latin text of those pronouncements issued by the emperors as far back as Hadrian which had the force of law (known as “constitutions”), and material from earlier compilations, all duly edited for continued use. This was, however, supplanted by a second edition published five years later, and that so thoroughly that the text of the first edition does not survive.
The second part of the project, known as the “Digests” in Latin and “Pandecta” in Greek, is a compilation of the opinions and writings of recognized jurists who had previously commented on the application of the law, and on discrepancies between contradictory laws. The third part, known as the Institutes (Institutiones), is a textbook, the use of which was made legally mandatory for the Empire’s two major law schools, one at Constantinople, and the other at Berytus, now called Beirut. Of course, the emperors did not cease to enact new laws once the project was completed in 534, and the fourth part of the Corpus is known as the “Novellae Constitutiones – the New Constitutions”, sometimes abbreviated (confusingly, for English speakers) as the “novels.” These underwent numerous revisions in the following centuries.
Like the older laws from which they were compiled, the official version of the Corpus was issued in Latin, which in the 6th century was still the legal language of the Roman Empire, even though the great majority of its subjects spoke Greek. (For this period, modern historians use the term “Eastern Roman Empire”, although it did not so distinguish itself at the time, and Justinian had recovered a good part of the territory which it had previously lost in the West.) However, in the reign of Emperor Heraclius (610-41), Greek officially replaced Latin as the language of law and governance. The Corpus Juris Civilis was then translated, and underwent various revisions and simplifications, until a final major revision at the end of the ninth century, known as the Basilika (imperial laws); this would remain the law of the Empire until its fall in 1453.
A page of an edition of the Digest printed in 1502; public domain image from Wikimedia Commons.
