One cause—­perhaps the main cause of this abstinence, and of the engagement to abstain entered into by Phraataces, was doubtless the unsettled state of things in Parthia itself.  The circumstances under which that prince had made himself king, though not unparalleled in the Parthian annals, were such as naturally tended towards civil strife, and as were apt to produce in Parthia internal difficulties, if not disorders or commotions.  Phraataces soon found that he would have a hard task to establish his rule.  The nobles objected to him, not only for the murder of his father, but his descent from an Italian concubine, and the incestuous commerce which he was supposed to maintain with her.  They had perhaps grounds for this last charge.  At any rate Phraataces provoked suspicion by the singular favors and honors which he granted to a woman whose origin was mean and extraction foreign.  Not content with private marks of esteem and love, he departed from the practice of all former Parthian sovereigns in placing her effigy upon his coins; and he accompanied this act with fulsome and absurd titles.  Musa was styled, not merely “Queen,” but “Heavenly Goddess,” as if the realities of slave origin and concubinage could be covered by the fiction of an apotheosis.  It is not surprising that the proud Parthian nobles were offended by these proceedings, and determined to rid themselves of a monarch whom they at once hated and despised.  Within a few years of his obtaining the throne an insurrection broke out against his authority; and after a brief struggle he was deprived of his crown and put to death.  The nobles then elected an Arsacid, named Orodes, whose residence at the time and relationship to the former monarchs are uncertain.  It seems probable that, like most princes of the blood royal, he had taken refuge in a foreign country from the suspicions and dangers that beset all possible pretenders to the royal dignity in Parthia, and was living in retirement, unexpectant of any such offer, when a deputation of Parthian nobles arrived and brought him the intelligence of his election.  It might have been expected that, obtaining the crown under these circumstances, he would have ruled well; but, according to Josephus (who is here, unfortunately, our sole authority), he very soon displayed so much violence and cruelty of disposition that his rule was felt to be intolerable; and the Parthians, again breaking into insurrection, rid themselves of him, killing him either at a banquet or on a hunting excursion.  This done, they sent to Rome, and requested Augustus to allow Vonones, the eldest son of Phraates IV., to return to Parthia in order that he might receive his father’s kingdom.  The Emperor complied readily enough, since he regarded his own dignity as advanced by the transaction; and the Parthians at first welcomed the object of their choice with rejoicings.  But after a little time their sentiments altered.  The young prince, bred up in Rome, and accustomed to the refinements