nce was scarcely settled upon the throne
when the whole of Western Asia was violently disturbed by the commotions
which shook the Roman Empire after the murder of Commodus. The
virtuous Pertinax was allowed to reign but three months (A.D. 193,
January--March). His successor was scarcely proclaimed when in three
different quarters the legionaries rose in arms, and, saluting their
commanders as "Emperors," invested them with the purple. Clodius
Albinus, in Britain; Severus, in Pannonia; and Pescennius Niger, in
Syria, at one and the same time claimed the place which the wretched
Julianus had bought, and prepared themselves to maintain their rights
against all who should impugn them. It seems that, on the first
proclamation of Niger, and before it had become evident that he would
have to establish his authority by force of arms, either the Parthian
monarch, or at any rate princes who were among his dependants, sent
to congratulate the new Emperor on his accession and to offer him
contingents of troops, if he required them. These spontaneous proposals
were at the first politely declined, since Niger expected to find
himself accepted joyfully as sovereign, and did not look to have
to engage in war. When, however, the news reached him that he had
formidable competitors, and that Severus, acknowledged Emperor at Rome,
was about to set out for the East, at the head of vast forces, he saw
that it would be necessary for him, if he were to make head against his
powerful rival, to draw together troops from all quarters. Accordingly,
towards the close of A.D. 193, he sent envoys to the princes beyond the
Euphrates, and especially to the kings of Parthia, Armenia, and Hatra,
entreating them to send their troops at once to his aid. Volagases,
under these circumstances, appears to have hesitated. He sent an answer
that he would issue orders to his satraps for the collection of a force,
but made no haste to redeem his promise, and in fact refrained from
despatching any body of distinctly Parthian troops to the assistance of
Niger in the impending struggle.

While, however, thus abstaining from direct interference in the contest
between the two Roman pretenders, Volagases appears to have allowed one
of his dependent monarchs to mix himself up in the quarrel. Hatra, at
this time the capital of an Arabian community, and the chief city of
central Mesopotamia (or the tract between the Sinjar and the Babylonian
alluvium), was a dependency of