Coincident with these troubles there was a new movement on the part of the Celtæ. Some time earlier Domitius, while still governing the regions adjacent to the Ister, had intercepted the Hermunduri (a tribe that for some unknown reason had left their native land and were wandering about in search of a different country), and he had settled them in a portion of Marcomania; next, encountering no opposition, he had crossed the Albis, cemented friendship with the barbarians on the other side, and set up an altar to Augustus to commemorate the event. Just now he had transferred his position to the Rhine, where, in pursuance of an intention to have his subordinates restore certain Cheruscian exiles, he had met with misfortune and had caused the other barbarians likewise to concieve a contempt for the Romans. This was, however, the extent of his operations during the year in question, for because of the Parthian war impending no chastisement was visited upon the rebels immediately. Nevertheless the war with the Parthians did not materialize. Phrataces heard that Gaius was in Syria, equipped with consular powers, and was furthermore uneasy about home interests in which even previously he had failed to discern a friendly feeling; hence he hastened to effect a reconciliation, secured on the proviso that he himself should depart from Armenia and his brothers remain over seas. [A.D. 2(_a. u._ 755)] Now the Armenians fell into conflict with the Romans the following year, in which Publius Vinicius and Publius Varus were consuls. The restraining influence of the fact that Tigranes had perished in some barbarian war and that Erato had resigned the sovereignty was nullified as soon as they were delivered to a Mede, Ariobarzanes, who had once come to the Romans in company with Tiridates. They accomplished nothing worthy of note save that a leader named Addon,[7] who was occupying Artagira, induced Gaius to come close up to the wall, pretending that he would reveal to him some secrets of the Parthian king, and then wounded him. In the consequent siege he maintained a prolonged resistance. When he was at last overthrown, not only Augustus but Gaius, too, assumed the title of imperator, and Armenia passed into the control of Ariobarzanes. Soon after the latter died, and his son Artabazus received it as the gift of Augustus and the senate. Gaius fell ill from the wound, and though he was not in any way robust and the condition of his health had, in fact, injured his mind, he now grew still more feeble. At length he begged leave to retire to private life, and it was his wish to take up his abode somewhere in Syria. Augustus, in the depth of grief, communicated his desire to the senate, and urged him to come at any rate to Italy and then do what he pleased. So Gaius resigned at once all the duties of his office and took a coastwise trading vessel to Lycia, where, at Limyra, he breathed his last. Prior to his demise the spark of Lucius's life had also paled.