Augustus was no great military leader, and had the good sense to recognize the fact. In his early years he relied heavily on Marcus Agrippa, his faithful friend, who had commanded the fleet at Actium. After Actium, Augustus took a personal lead in only one further campaign, the Cantabrian War of 26-25 BC in Spain; but even there it was one of his generals who brought the war to a successful conclusion.
The reign was marked nevertheless by some notable Roman successes. First and most important was the conquest of Egypt in 30 BC. That province soon became the principal source of the crucial free grain supply for the population of Rome. Augustus achieved a diplomatic victory in 20 BC, when he recovered the legionary standards captured by the Parthians at the disastrous battle of Carrhae in 53 BC. It was frontiers, however, which were the main military preoccupation of the reign. In the east, the Syrian desert and River Euphrates formed a natural boundary. To the north, Julius Caesar had already conquered Gaul in the 50s and established a new frontier along the Rhine. Augustus made the Danube his Balkan frontier after some hard-fought campaigns conquering the Alpine tribes and pacifying the northern Balkans. He then had to decide how best to carry this line to the North Sea. Following the Danube and Rhine to their sources created an awkward re-entrant in the Alps; a much shorter frontier would result if Roman rule could be carried forward to the Elbe. This Augustus determined to achieve, and in 1 2 BC he gave his stepson Drusus command of the Rhine legions with orders to advance to the Elbe. When Drusus died in 9 BC the task was transferred to his other stepson Tiberius. The work was steadily carried forward by others when Tiberius went into self-imposed exile on Rhodes, but Tiberius resumed command in AD 4. He was planning to conquer Bohemia and Moravia in AD 6 when he was called away to deal with a serious Balkan revolt. Then in AD 9 came the disaster of the Teutoburg Forest.
Quintilius Varus, commander of the Rhine legions, had spent the summer of AD 9 on the banks of the Weser. Germany was by now considered pacified and Varus took no special precautions when moving back to winter quarters on the Rhine. In September that year he was ambushed by the Germans in the Teutoburg Forest (near Osnabruck) and his three legions annihilated. Tiberius moved swiftly to the Rhine frontier to prevent any German invasion of Gaul, but Augustus himself was deeply shocked. It was said that for several months afterwards he went in mourning, cutting neither his beard nor his hair, and from time to time hitting his head against a door, crying ‘Quintilius Varus, give me back my legions ! ‘
Plans for an Elbe frontier were abandoned, and so cautious did Augustus become that when he died five years later, he left Tiberius a document in his own hand advising him to keep the empire within its present frontiers.
The military establishment
It seems curious that the loss of three legions could so seriously upset Augustus, but there was no reserve army, and reinforcement of one frontier meant transfer of legions from another. Augustus’s overall policy was to keep the military establishment at the minimum necessary to ensure peace within the empire and guard the frontiers. Soon after Actium, he reduced the number of legions to 28, most of which were stationed on the imperial frontiers. After the Varus disaster eight of the remaining 25 legions were based along the Rhine, seven along the Danube, and four in Syria. Their control was crucial to Augustus’s power. The soldiers swore loyalty to him as imperator, not to the senate or the state. He was the first to give them fixed terms of service and pay. To further consolidate his position Augustus established the Praetorian Guard, nine elite cohorts, each of 500 (or perhaps 1 000) men, based in Rome and its vicinity, whose sole function was to protect the emperor.
The eventual heir
Tiberius retired to the island of Rhodes, where he lived quietly for almost eight years. In 2 BC Julia was banished to Pandateria for adultery and her marriage to Tiberius dissolved, but Gaius Caesar, the heir apparent, would not permit him to return to the capital. For a while Tiberius went in fear for his life. Then in August AD 2 he was allowed back to Rome on the firm understanding that he took no part in public affairs.
Within days of his arrival news came of Lucius’s death in Marseilles, followed early the next year by that of Gaius. This left Augustus without an heir, and opened the way for Livia to plead her son’s cause. Quite what Augustus felt about Tiberius is unclear. One tradition has Augustus exclaim on his deathbed ‘Alas for the Roman people, to be ground by jaws that crunch so slowly! ‘ He certainly thought Tiberius austere and stiff, and when adopting Tiberius on 27 June AD 4, he added the words ‘This I do for reasons of state’. Tiberius was an adequate successor, perhaps, but not one he embraced with any enthusiasm.
Soon after his adoption Tiberius was back with the legions on the Rhine, campaigning deep into Germany. Then in AD 6 he went to suppress a serious Balkan revolt. Hardly was that over than news arrived of Varus’s disaster in Germany, and Tiberius was back on the Rhine shoring up the defences. He returned to Rome to celebrate a triumph in October AD 1 2, and remained in Italy during Augustus’s final months. Of his military prowess there was no doubt, but he still had almost no experience of running the empire. Nor was much effort made to give him any. Tiberius was on his way back to the Balkans when an urgent message called him to Augustus’s deathbed.
The first decade
Drusus and Germanicus played an important role during Tiberius’s early years as emperor, Germanicus drawing considerable prestige from his ancestry: not only was he adoptive son of Tiberius, but he was also great-nephew of Augustus, had inherited Julian blood from his mother Antonia, and was married to Augustus’s grand-daughter Agrippina the elder. Livia, on the other hand, was a less welcome partner in power, and Tiberius took steps to limit her influence. She had been made Augusta in Augustus’s will; but Tiberius refused to allow her the title ‘Mother of her Country’ or the honour of a lictor.
Germanicus remained with the Rhine army from AD 14 to 16, leading the legions deep into Germany in successive campaigns. He managed to recover two of the three legionary standards lost at the Teutoburg forest, and buried the remains of the Roman dead. There was no longer any idea of permanently advancing the Roman frontier east of the Rhine, however, and Tiberius cut short expensive and unnecessary operations by recalling Germanicus to Rome. He celebrated a triumph there on 26 May 17, and the following year became Tiberius’s colleague as consul.