From the days of Diocletian the style of architecture which we call Byzantine, for want of a better name, had been slowly developing from the old classic forms, and many of the emperors of the fourth and fifth centuries had been given to building. But no previous monarch had combined in such a degree as did Justinian the will and the power to launch out into architectural experiments. He had at his disposal the hoarded treasures of Anastasius, and his tastes were as magnificent as those of the great builders of the early empire, Augustus and Nero and Hadrian. All over the empire the monuments of his wealth and taste were seen in dozens of churches, halls of justice, monasteries, forts, hospitals, and colonnades.
St. Sophia (Hagia Sophia)
Even in the more secluded or outlying portions of the empire, any fine building that is found is, in two cases out of three, one of the works of Justinian. Not merely great centres like Constantinople or Jerusalem, but out-of-the-way tracts in Cappadocia and Isauria, are full of his buildings. Even in the newly-conquered Ravenna his great churches of San Vitale, containing the celebrated mosaic portraits of himself and his wife, and of St. Apollinare in the suburb of Classis, outshine the older works of the fifth-century emperors and of the Goth Theodoric.
Justinian’s churches, indeed, are the best known of his buildings. In Oriental church-architecture his reign forms a landmark: up to his time Christian architects had still been using two patterns copied straight from Old Roman models. The first was the round domed church, whose origin can be traced back to such Roman originals as the celebrated Temple of Vesta—of such the Church of the Holy Sepulchre at Rome may serve as a type. The second was the rectangular church with apses, which was nothing more than an adaptation for ecclesiastical purposes of the Old Roman law-courts, and which had borrowed from them its name of Basilica. St. Paul’s Outside the Walls, at Rome is a fair specimen. Justinian brought into use for the first time on a large scale the combination of a cruciform ground-plan and a very large dome. The famous Church of St. Sophia may serve as the type of this style. The great cathedral of Constantinople had already been burnt down twice, as we have had occasion to relate: the first time on the eve of the banishment of John Chrysostom, the second in the great “Nika” riot of 532. Within forty days of its destruction Justinian had commenced preparations for rebuilding it as a monument of his triumph in the civil strife. He chose as his architect Anthemius of Tralles, the greatest of Byzantine builders, and one of the few whose names have survived.
Justinian was almost as great a builder of forts as of churches, but his military works have for the most part disappeared. It may give some idea of his energy in fortifying the frontiers when we state that the Illyrian provinces alone were protected by 294 forts. Some were single towers, but many were elaborate fortresses with outworks, and all had to be protected by garrisons.
The Roman law, as he received it from his predecessors was an enormous mass of precedents and decisions, in which the original basis was overlaid with the various and sometimes contradictory rescripts of five centuries of emperors. Several of his predecessors, and most especially Theodosius II., had endeavoured to codify the chaotic mass and reduce it to order. But no one of them had produced a code which sufficed to bring the law of the day into full accord with the spirit of the times. It was no mean work to bring the ancient legislation of Rome, from the days of the Twelve Tables down to the days of Justinian, into strict and logical connection with the new Christian ideas which had worked their way into predominance since the days of Constantine. Much of the old law was hopelessly obsolete, owing to the change in moral ideas which Christianity had introduced, but it is still astonishing to see how much of the old forms of the times of the early empire survived into the sixth century. Justinian employed a commission, headed by the clever but unpopular lawyer Tribonian, to draw up his new code. The work was done for ever and a day, and his “Institutes” and “Pandects” were the last revision of the Old Roman laws, and the starting-point of all systematic legal study in Europe, when, six hundred years later, the need for something more than customary folk-right began to make itself felt, as mediaeval civilization evolved itself out of the chaos of the dark ages.
(Source: “The Byzantine Empire”, by C. W. C. Oman)
Roman Emperor Justinian (Flavius Petrus Sabbatius Iustinianus Augustus)
Research-Selection for NovoScriptorium: Anastasius Philoponus