The army of Agrippa in Illyria protected the rear of Drusus, who was able to drive the Alpine tribes back through the passes to the Northern face of the Alps, where they found the army of Tiberius ready for them. The victory was so complete that the very names of these tribes disappear from history; squeezed between two Roman armies they were doubtless exterminated. Horace wrote an official ode on the occasion, comparing Drusus to a young eagle or lion; and in a complimentary ode to Augustus on another occasion, compared the charge of Tiberius to the impetuous floods of the Aufidus, his native river. The northern slopes of the Western Alps were now secured to Rome; there was no longer any danger of Gallic intrigues stimulated by the restless Helvetii, but the work was by no means done. Augustus seems to have remained for some time in Gaul studying its social conditions, Agrippa remained in the Illyrian district, Drusus was sent to the lower Rhine, and Tiberius, as far as we can gather, remained at Rome. Profiting by the experience gained in the recent war, Drusus determined to repeat the strategy of Tiberius, and again to hem in an elusive enemy between two Roman armies; he himself marched up the Lippe, making a point on the Weser, somewhere near Paderborn, his objective, and at the same time he sent a flotilla down the Rhine, with instructions to ascend the mouth of the Weser, and thus cut off the flight of the Germans. The first attempt failed, the fleet being dispersed by storms; it was reserved for Tiberius himself to succeed at a later date in this combined movement. In the following year Drusus advanced to the Weser, and on his return established a permanent outpost at Aliso, fifty miles up the Lippe; this was the period of the death of Agrippa, whose command in Pannonia was taken over by Tiberius. We know but little of the operations of Tiberius in Pannonia at this time, except that they were successful, and that the ring of Roman provinces was now completed along the East coast of the Adriatic, uniting Greece and Macedonia with Italy. In B.C. 10 Augustus returned to Gaul; Drusus consecrated a temple in his honour at Lyons, and the worship of the Roman Empire personified in Augustus was officially substituted for the Druidical religion, in whose priesthood Augustus saw the irreconcilable enemy of Rome. After this ceremony Drusus again crossed the Rhine and penetrated as far as the Elbe; on his return he met with the accident which caused his death, and elicited that touching illustration of affection on the part of Tiberius, to which reference has already been made.