1911 Encyclopædia Britannica/Cassius, Avidius
CASSIUS, AVIDIUS (d. A.D. 175), Roman general, a Syrian by birth, lived during the reign of Marcus Aurelius. He especially distinguished himself during the Parthian War (A.D. 162–165), at the conclusion of which he was apparently appointed military governor of Asia, though the actual extent of his jurisdiction is doubtful. In 172 he was sent to Egypt, where he put down a dangerous rising of the Bucolici, the robber herdsmen of the delta of the Nile, after which he returned to Syria. In 175 the emperor Aurelius fell ill, and his wife Faustina, to secure her position in case of his death, offered her hand and the throne to the successful general. A rumour of Aurelius's death having reached Syria, Cassius, without waiting for confirmation, proclaimed himself emperor; when the report proved false, it was too late for him to draw back, and he accordingly prepared for war. The senate declared him a public enemy, although Aurelius even then expressed the hope that he might have the opportunity of pardoning him. Deploring the necessity for taking up arms against his trusted officer, Aurelius set out for the east. While in Illyria, he received the news that Cassius had been slain by his own officers. The murderers offered his head to Aurelius, who refused to admit them, and ordered its immediate burial.
See Dio Cassius lxxi. 2-4, 17, 22-28, 30, 31; Fronto, Letters, i. 6; Lives of Marcus Aurelius, Verus and Commodus in the Scriptores Historiae Augustae, and the special biography of Avidius Cassius in the same by Vulcacius Gallicanus. The various letters and documents in the last-named are generally considered spurious, and the portions of the narrative founded on them consequently untrustworthy. See also article in Pauly-Wissowa's Realencyclopädie, ii. pt. 2 (1896).