Tacitus’ assessment at Ann. 4.32.2 that Tiberius was uninterested in extending the empire, combined with instructions supposedly left by Augustus for Tiberius to that end (Ann. 1.11.4), prejudice our opinion of Tiberian foreign policy, especially in contrast with the early career of Octavian/Augustus. Augustus’ expansion of the empire was no doubt great, but was mostly driven by the need to consolidate previously held Roman territories. The addition of Egypt was due to the fortuitous alliance of Antony and Cleopatra and their subsequent downfall. And much of the territory won north of Italy was secured by Tiberius himself. It then remains to ask, why did Tiberius, a skilled general and agent of Augustan expansion, become the poster child for retrenchment?
The most problematic aspect of Tiberian imperial policy concerns his abandonment of Germany and the recall of Germanicus. According to the traditional view, Augustus had every intention of subduing all of Germany up to the Elbe. But after the revolts in Illyricum in 6-9 A.D. and the clades Variana, Augustus became more conservative in his approach to the region. While some have attributed this to the influence of Tiberius after his adoption in 4 A.D., it more likely stems from Roman ignorance of the region, its geography, and nature of the tribes who traveled through it. It had taken Rome over two hundred years to gain control of the Iberian Peninsula, and that area was bordered by Roman Gaul and the sea. It is no wonder that Germania, which bordered territories never conquered by the Romans, would be so difficult to master. As Brunt states in his assessment of Agrippa’s map in the Porticus Vipsania: “Agrippa himself evidently had no notion of the size of the land-mass east of the Rhine” (1963: 175). Moreover, while Domitius Ahenobarbus planted an altar along the Elbe, there is no evidence of permanent military settlements beyond the Weser (Timpe 2008: 210).
Instead of having a decidedly imperialist plan, Augustus reacted to situations in ways which saved face for the Roman state. Rich asserts, “An adequate account of Augustus’ external policies should allow for their evolution over time” (2003: 344-345). Thus, even if Tiberius may have been instructed not to expand the empire, he was efficient in dealing with problems that arose, most notably in Africa with Tacfarinas, and in Gaul under Florus and Sacrovir. Not only did Tiberius not lose any territory which had been held at the death of Augustus, but he annexed the kingdoms of Cappadocia and Commagene (and possibly Cilicia (Goodyear (1981: 321)) in 17 A.D., turning them into Roman provinces (Tac. Ann. 2.42, 2.56).
Moreover, Augustus preferred when possible to resolve conflicts by diplomacy rather than open warfare, most notably, in his dealings with Parthia. Tiberius’ policy in Germany followed this model, playing various tribes against each other. Through such means, Tiberius not only brought about the downfall of Maroboduus, but also of his pawn against Maroboduus, Catualda. Tacitus tells us (Ann. 2.88) that these tactics also helped to eliminate Arminius, who, aiming at the throne, was killed by the treachery of his countrymen – dolo propinquorum cecidit. Thus through shrewd diplomacy and manipulation, Tiberius had destroyed the two greatest enemies of Rome in Germany, Maroboduus and Arminius.
If Augustus exhibited flexibility in his attitude towards crises within the empire and preferred to use showy diplomacy rather than risk his troops, Tiberius merely continued this policy. Strabo, writing in the context of Augustus’ pacification of the empire, states as much (6.4.2). Velleius seconds this opinion. Moreover, as Rich observes, “Velleius [2.126.3] includes among the blessings of Tiberius’ reign the universal diffusion of pax augusta (the only occurrence of the phrase in a literary source)” (2003: 333 n. 25). Given the role Tiberius played in ensuring and continuing Augustus’ foreign policy, perhaps the term pax tiberiana is more apt.
Augustus and After