Although Theodosius for the time effectually repressed the invasions of the hostile nations, and restored the province in its integrity, his success left no permanent result behind it; and within forty years after the re-establishment of the province, the Romans were notwithstanding obliged finally to abandon the island. This arose from two causes:—the yearly increasing pressure of the Barbarians upon the military resources of the Empire required the withdrawal of the troops from those distant provinces which were less easily maintained; and the same cause which concentrated the attention of the Emperor upon the defence of the nearer frontiers, and led him to neglect those more remote, rendered the assumption of the imperial authority almost the inevitable consequence of an isolated command, and a temptation too great to be resisted. Had these usurpers been content to remain in possession of Britain alone, they might, in the distracted state of the Empire, have been able to have maintained their position, and an insular dominion been founded which would have greatly affected the future history and fortunes of Britain; but they aimed at the possession of the whole of the western diocese of Gaul, Spain, and Britain, and in grasping at too much effected their own ruin. Their ambition led to the troops no sooner proclaiming their general Emperor, than they were withdrawn from Britain and conveyed into Gaul to support the usurper’s ambitious aim, and the province was thus left undefended to the incursions of the hostile nations. [Sidenote: A.D. 383. Revolt by Maximus.] The first of these insular Emperors after the war of Theodosius was Clemens Maximus, an Iberian or Spaniard by birth, who had served under Theodosius in Britain, and was now, twelve years later, in command of the Roman army there. Taking advantage of the unpopularity of the Emperor Gratian with the army owing to favour shown to the Alans, and jealous of the elevation of the younger Theodosius to a share in the Empire, he excited the army in Britain to revolt, and was proclaimed Emperor in the year 383. In the following year he repressed the incursions of the Picts and Scots,[96] and forced the hostile nations to yield to his power. He then crossed over to Gaul with the army of Britain, slew the Emperor Gratian, and after maintaining himself in Gaul for four years, he entered Italy, and was finally defeated and slain by the Emperor Theodosius at Aquileia, in the year 388. [Sidenote: A.D. 387. Withdrawal of Roman troops from Britain; first devastation of province by Picts and Scots.]