Dexippus in Harpers Dictionary of Classical Antiquities
P. Herennius, a Greek historian and rhetorician, born in Attica in the third century A.D. He held high office in Athens, and in the year 262, when the Goths invaded Greece, distinguished himself against them. He died about A.D. 280. Photius gives some account of three historical works by Dexippus-a history of Macedonia from the time of Alexander the Great; a general chronological history from the earliest times down to the year A.D. 268; and, finally, an account of the wars with the Goths in which Dexippus had himself fought. The fragments of these works, which are fairly numerous, are included in the collection of Scriptores Historiae Byzantinae.
Dexippus in Wikipedia
Publius Herennius Dexippus (Greek: Δέξιππος, ca. 210–273), Greek historian, statesman and general, was an hereditary priest of the Eleusinian family of the Kerykes, and held the offices of archon basileus and eponymous in Athens.
When the Heruli overran Greece and captured Athens (269), Dexippus showed great personal courage and revived the spirit of patriotism among his fellow-countrymen. A statue was set up in his honour, the base of which, with an inscription recording his services, has been preserved. It is remarkable that the inscription is silent as to his military achievements. Photius (cod. 82) mentions three historical works by Dexippus, of which considerable fragments remain:
1. The Events after Alexander, apparently an epitome of a work by Arrian
2. The Scythica, a history of the wars of Rome with the Goths (called Scythians in archaizing language) in the 3rd century
3. The Chronike Historia in twelve books, probably covering a thousand years to the reign of the emperor Claudius Gothicus (270)
The Chronicle was continued by Eunapius of Sardis, who opens his own history with a critique of his predecessor. The Chronicle also appears to be the primary source of the Historia Augusta between 238 and 270, but Paschoud has demonstrated that the author of the Historia Augusta sometimes attributes material to Dexippus falsely, and so this evidence must be used with caution.
Photius speaks very highly of the style of Dexippus, whom he calls a second Thucydides.