Accounts of the Rebuilding of The Hagia Sophia (558–62)105 Agathias of Myrina
Agathias, Hist. V, 9, 2–5: He [Justinian] showed particular concern for the Great Church of God which he rebuilt in a conspicuous and admirable form from the very foundations after it had been burnt down by the populace, and endowed it with exceedingly great size, a majestic shape and an adornment of various quarried materials. He compacted it of baked brick and mortar, and in many places bound it together with iron, but made no use of wood so that the church should no longer prove combustible. The architect and creator of all these things was that Anthemius whom I mentioned not long ago. When, as a result of the earthquake,106 the church had lost the central part of the roof-the part that towers over all the others-the emperor repaired it in a more secure fashion and raised it to a greater height. Since Anthemius had long been dead, Isidore the Younger and the other engineers reviewed among themselves the former design and, by reference to what had remained, they judged the part that had fallen down, i.e., its nature and its faults. They left the east and west arches as they were in their former places, but in the case of the north and south ones they extended inward that part of the construction which lies on a curve and gradually increased its width so as to make them [the north and south arches] agree more closely with the others and observe the harmony of equal sides. In this way they were able to reduce the unevenness of the void and to gain a little on the extent of the space, i.e., that part of it which produced a rectangular figure. Upon these [new] arches they set up once again that circle or hemisphere (or whatever alse they call it) which dominates the centre of the building. As a result, the dome naturally became more even and well-curved, conforming altogether to the [correct geometrical] figure. It was narrower and steeper so that it did not strike spectators with as much amazement as before, but it was far more securely set up.

Theophanes of Byzantium
Theophanes, A.M. 6051, pp. 232–33:107 On May 7th of this year [558], a Tuesday, in the 5th hour, while the dome of the Great Church was being repaired-for it had been cracked by the preceding earthquakes- and while the Isaurians108 were at work, the eastern part of the vault (prohupostolê) of the holy sanctuary fell down and crushed the ciborium, the altar-table and the ambo. The engineers were censured because, avoiding the expense, they had not made the suspension [secure] from below, but had tunnelled the piers upholding the dome, and for this reason they had not held. Having grasped this, the most-pious emperor erected new piers to receive the dome,109 and so the dome was built and raised by more than twenty feet in height as compared to the original Structure.

Malalas
Malalas, p. 495: In the same indiction [562/3]110 took place the second consecration of the most-holy Great Church. As compared to its old form, the dome was made thirty feet higher and they also made two additional arches (kamarai), i.e., the northern and the southern one.

Notes
105 Cf. G. Millet, "La coupole primitive de Ste. Sophie," Revue belge de pilologie et d'histoire, II (1923), 599 ff.; K.J. Conant, "The First Dome of St. Sophia and its Rebuilding," Bulletin of the Byzantine Institute, I (1946), 71 ff.
106 The earthquake occurred in December 557, and the collapse of the dome in 558.
107 This passage probably derives from the complete Chronicle of Malalas, now lost. It also appears, with minor variations, in the abbreviated Malalas, CSHB, pp. 489 f. and in other chronicles. Cedrenus, CSHB, I, 676 f. adds: "He [Justinian] also made outside the church the four spiral ramps opposite the interior piers. These he planted in the ground and raised as far as the dome so as to buttress the arches. At the same time he made the altar-table, an incomparable work."
108 Cf. C. Mango, "Isaurian Builders," Polychronion: Fetschrift F. Dölger (Heidelberg, 1966), pp. 358 ff.
109 Incorrect.
110 The reconscration was celebrated on December 24, 562.

Copyright: Cyril A. Mango, The Art of the Byzantine empire, 312–1453: Sources and Documents, Englewood Cliffs, 1972.