Of the personal influences to which Tiberius was submitted in his youth the one best known to us is that of Horace, who incidentally throws a light upon his character as a young man. In the year 21 B.C. Augustus made a progress to the East, visiting notable cities on the way, and regulating their affairs. The chief object of the tour was, however, to settle the Eastern frontier of the Empire. Syria was to Rome what the North-West Provinces of India are to England; Herod and Aretas of Arabia with the princes of Armenia played the part of the Ameer of Afghanistan; they were the buffer states between Roman civilization and the aggressive powers of Central Asia. Their fidelity was by no means beyond suspicion, and from the mountains of Armenia, all along the west of the Euphrates down to the borders of Egypt, continuous intriguing prevailed, every ambitious kinglet making use of one or the other of the great powers to strengthen his position against his rivals. The strongest of these chieftains were the rulers of Armenia and Herod the Idumæan; the former were unquestionably treacherous, and their proximity to the Parthians rendered them peculiarly liable to wavering; the latter played skilfully for his own hand. So long as Rome was strong, Herod was her obedient servant, but if Rome showed signs of weakness, Herod had no scruples against making friends with a stronger power in order to further his own ends. Since Cæsar had conquered Pharnaces, the son of Mithridates, by his mere apparition, the prestige of Rome in the East had been considerably damaged. The expeditions of Antonius against the Parthians had been unsuccessful, and a serious catastrophe had only been averted by the valour of his lieutenant, Ventidius Bassus, a former mule-driver; by submitting Herod to the demands of Cleopatra’s cupidity, he had to some extent alienated the Idumæan, and encouraged him to distrust Roman politicians. Now that the Spanish war was over and the Western half of the Empire in good order, Augustus wisely determined to study his Eastern questions on the spot, and make such a demonstration of power as would determine the judgment of waverers in favour of Rome. The plan of operations was to send an army through Asia Minor into Armenia, and thence if necessary along the Tigris into Parthia, while the possible allies of the Parthians in Syria were to be overawed simultaneously by the presence of the Emperor. The command of the army destined for Armenia was given to Tiberius, now twenty-one years of age. Both operations were successful; there was not much fighting, but the Parthians saw that Rome was in earnest, and made terms, sending back the standards which had been taken from Crassus some thirty years before; the Roman party in Armenia was strengthened by a change of rulers, and Tiberius returned in triumph. His first essay in war and diplomacy was successful.