II. MAGNUS MAXIMUS, a native of Spain, who had accompanied Theodosius on several expeditions and from 368 held high military rank in Britain. The disaffected troops having proclaimed Maximus emperor, he crossed over to Gaul, attacked Gratian (q.v.), and drove him from Paris to Lyons, where he was murdered by a partisan of Maximus. Theodosius being unable to avenge the death of his colleague, an agreement was made (384 or 385) by which Maximus was recognized as Augustus and sole emperor in Gaul, Spain and Britain, while Valentinian II. was to remain unmolested in Italy and Illyricum, Theodosius retaining his sovereignty in the East. In 387 Maximus crossed the Alps, Valentinian was speedily put to flight, while the invader established himself in Milan and for the time became master of Italy. Theodosius now took vigorous measures. Advancing with a powerful army, he twice defeated the troops of Maximus--at Siscia on the Save, and at Poetovio on the Danube. He then hurried on to Aquileia, where Maximus had shut himself up, and had him beheaded. Under the name of Maxen Wledig, Maximus appears in the list of Welsh royal heroes (see R. Williams, _Biog. Dict. of Eminent Welshmen_, 1852; "The Dream of Maxen Wledig," in the _Mabinogion_). Full account with classical references in H. Richter, _Das weströmische Reich, besonders unter den Kaisern Gratian, Valentinian II. und Maximus_ (1865); see also H. Schiller, _Geschichte der römischen Kaiserzeit_, ii. (1887); Gibbon, _Decline and Fall_, ch. 27; Tillemont, _Hist. des empereurs_, v. III. MAXIMUS TYRANNUS, made emperor in Spain by the Roman general, Gerontius, who had rebelled against the usurper Constantine in 408. After the defeat of Gerontius at Arelate (Arles) and his death in 411 Maximus renounced the imperial title and was permitted by Constantine to retire into private life. About 418 he rebelled again, but, failing in his attempt, was seized, carried into Italy, and put to death at Ravenna in 422. See Orosius vii. 42; Zosimus vi. 5; Sozomen ix. 3; E. A. Freeman, "The Tyrants of Britain, Gaul and Spain, A.D. 406-411," in _English Historical Review_, i. (1886). IV. PETRONIUS MAXIMUS, a member of the higher Roman nobility, had held several court and public offices, including those of _praefectus Romae_ (420) and _Italiae_ (439-441 and 445), and consul (433, 443). He was one of the intimate associates of Valentinian III., whom he assisted in the palace intrigues which led to the death of Aëtius in 454; but an outrage committed on the wife of Maximus by the emperor turned his friendship into hatred. Maximus was proclaimed emperor immediately after Valentinian's murder (March 16, 455), but after reigning less than three months, he was murdered by some Burgundian mercenaries as he was fleeing before the troops of Genseric, who, invited by Eudoxia, the widow of Valentinian, had landed at the mouth of the Tiber (May or June 455).