Marcellinus Comes (died ~534 AD) spent most of his life in Constantinople and only wrote one text which survives -
Annales, a continuation of Eusebius's Ecclesiastical History.
Marcellinus Comes' Annales spans from 379 to 534 CE with additions to 566 CE by an unknown author
(wikipedia).
Croke (1995:xxiv) notes that
Marcellinus' sources for Portents (earthquakes, eclipses etc.) was
a previous chronicle which contained predominantly Constantinopolitan events
which was likely based on the so-called 'City Chronicle' of Constantinople.
For the Monaxius and Plinta Quake, the ultimate source was probably
a letter written by Praulius who was the Bishop of Jerusalem in 419 CE.
Croke (1995:xix-xx) describes Marcellinus Comes' life as follows:
Count Marcellinus, or Marcellinus comes as he is usually designated, is one of the lesser literary figures of late antiquity. He is known almost exclusively as the author of anannalistic chronicle continuing that of Jerome from AD 379 to 518, which Marcellinus himself later updated to 5341. He composed his chronicle in Constantinople and it was while the Roman senator Cassiodorus was there in 550/1, as a refugee from Justinian's war against the Ostrogoths, that he acquired a copy of it. If Cassiodorus did not actually meet Marcellinus then he certainly knew something about him, for in his Institutiones, a handbook for monks, he tells us that Marcellinus was an Illyrian:[Jerome] has been followed in turn by the aforesaid Marcellinus the Illyrian who is said to have acted first as cancellarius of the patrician Justinian, but who later, with the Lord's help upon the improvement of his employer's civil status, faithfully guided his work from the time of the emperor (Justin) to the beginning of the thumphant rule of the emperor Justinian.2By 'illyrian' Cassiodorus meant from the late Roman prefecture of Illyricum, more precisely from one of its Latin-speaking Balkan provinces. At some point (c.500) he must have migrated to the eastern imperial capital, Constantinople, as did so many of his ambitious contemporaries. At Constantinople Marcellinus was eventually able to secure a prestigious position as cancellarius to a fellow-illyrian, the patrician Justinian, in the early 520s. As a cancellarius Marcellinus was comes and of senatorial status (virclarissimus) — the titles he records in the preface to his chronicle. Marcellinus apparently left his court post before Justian became emperor in 527.
In this subsequent period he probably devoted himself to literary pursuits. Marcellinus, who is generally reticent about his own life and views (not that a chronicle gave him much scope to display his individuality), tells us in the preface that his chronicle originally covered the period 379 to 518. Since it was common practice for chroniclers to update their works it is reasonable to assume that the first edition appeared in or soon after 518, that is to say, a few years before Marcellinus entered the service of Justinian. The second edition of the chronicle, the version which survives, continued the work to 534. It was arguably written as a tribute to his former employer Justinian on the occasion of the triumph over the Vandals in Africa which was celebrated at Constantinople in 534. As with other similar chronicles, that of Prosper for example, the purpose of the second edition was merely to up-date the record. Except for minor necessary changes it is unlikely that there were any substantial additions or modifications to what had been already written, for the period 379—518.
Apart from the chronicle, Marcellinus wrote several other works which have not survived, despite the fact that Cassiodorus also recommended these in his handbook:Marcellinus too has traversed his journey's path in laudable fashion, completing four books on the nature of events and the locations of places with most decorous propriety; I have likewise left this work for you (Inst. 1.17.1).It is deduced from this statement that there were two other works of Marcellinus (not one work described in two different ways, as sometimes suggested), both in four books, which were known to Cassiodorus: (1) a detailed work on the nature of temporal events and the location of places (de temporum qualitatibus et positionibus locorum) and (2) another on the topography of Constantinople and Jerusalem. The chronicle itself displays the author's interest in both Constantinople (passim) and the 'Holy Land' (s.a. 415,419, 439, 443, 453, 516) and it would not be surprising if his books on Jerusalem, as well as those in the other work on the locations of places, were firmly rooted in first-hand observation — as Cassiodorus seems to imply. Moreover, it is quite possible that Marcellinus traveled as far afield as Dara on the Persian frontier on his sojourn. In any case the only surviving fragment of these works is a detailed description of Dara which appears to derive from the books 'on the locations of places'.3
Marcellinus too, concerning whom I have already spoken, should be read with equal care; he has described the city of Constantinople and the city of Jerusalemin four short books in considerable detail (Inst. 1.25.1)
Except for the facts that Marcellinus was Illyrian, wrote a chronicle in about 518/9, was a cancellarius to Justinian before 527, then retired from imperial service, updated his chronicle to 534 and was responsible for two other works now lost except for all this, we know nothing else about the man. We have no idea when he was born or died, when he came to Constantinople, what sort of education he had and where he stood in the society of his day. Nonetheless the evidence of the chronicle itself permits a sketchy outline of his background and culture.Footnotes1 In general: Mommsen, 1894. 42; Holder-Egger. 1877, 49—56; SchanzjHosiuslKruger, 1920. 112; Moricca, 1943, 1363; PLRE 2: 711 s.v. Marcellinus 9'.
2 lnst. I. 17. 2. as interpreted in Croke, 1982c.
3 Croke, 1984, 77—88.