Volagases survived his defeat by Severus about ten or eleven years. For this space Parthian history is once more a blank, our authorities containing no notice that directly touches Parthia during the period in question. The stay of Severus in the East during the years A.D. 200 and 201, would seem to indicate that the condition of the Oriental provinces was unsettled and required the presence of the Imperator. But we hear of no effort made by Parthia at this time to recover her losses--of no further collision between her troops and those of Rome; and we may assume therefore that peace was preserved, and that the Parthian monarch acquiesced, however unwillingly, in the curtailment of his territory. Probably internal, no less than external, difficulties pressed upon him. The diminution of Parthian prestige which had been brought about by the successive victories of Trajan, Avidius Cassius, and Severus must have loosened the ties which bound to Parthia the several vassal kingdoms. Her suzerainty had been accepted as that of the Asiatic nation most competent to make head against European intruders, and secure the native races in continued independence of a wholly alien power. It may well have appeared at this time to the various vassal states that the Parthian vigor had become _effete_, that the qualities which had advanced the race to the leadership of Western Asia were gone, and that unless some new power could be raised up to act energetically against Rome, the West would obtain complete dominion over the East, and Asia be absorbed into Europe. Thoughts of this kind, fermenting among the subject populations, would produce a general debility, a want both of power and of inclination to make any combined effort, a desire to wait until an opportunity of acting with effect should offer. Hence probably the deadness and apathy which characterize this period, and which seem at first sight so astonishing. Distrust of their actual leader paralyzed the nations of Western Asia, and they did not as yet see their way clearly towards placing themselves under any other guidance. Volagases IV. reigned till A.D. 208-9, dying thus about two years before his great adversary, who expired at York, February 4, A.D. 211. CHAPTER XXI. _Struggle between the two Sons of Volagases IV., Volagases V. and Artabanus. Continued Sovereignty of both Princes. Ambition of Caracallus. His Proceedings in the East. His Resolve to quarrel with Parthia. First Proposal made by him to Artabanus. Perplexity of Artabanus. Caracallus invades Parthia. His Successes, and Death. Macrinus, defeated by Artabanus, consents to Terms of Peace. Revolt of the Persians under Artaxerxes. Prolonged Struggle. Death of Artabanus, and Downfall of the Parthian Empire._