The voluntary exile of Tiberius left Augustus in a difficult position. By not removing Tiberius’s power, he left his son-in-law a way back to Rome’s political and military leadership. He also did not divorce Julia from him. But he seems to have proceeded with his plans as if Tiberius was no longer a part of them.
His first step was to once more take the consulship for 5 BC. He had not been consul since 23 BC. His standing aside from the consulship had one of the ways he negotiated his power relations over the previous seventeen years. He was 57 years old, not old by modern standards, but in the ancient world those few who reached their early sixties were unusual and in some societies rewarded and supported. His taking of the consulship was an assertion that whatever had happened with Tiberius and however old he was, he was still in charge.
His next step was to further advance Gaius. He was given a military command, which might have been notional, and declared princeps iuventutis (leader of youth). The following year, all the same honours were given to Lucius: it was clear that the boys were to be advanced together (Dio, 55.9).
In 2 BC, Augustus took the consulship again. Gaius reached eighteen and was starting to seem a more plausible leader. Lucius was fifteen. The reason for the consulship was either to usher in further honours for the boys or to open the Temple of Mars Ultor in the Forum of Augustus.
The Temple had been promised by the young Octavian to mark the defeat of the assassins. It was given new impetus by the return of the Parthian standards in 20 BC. The standards were to be displayed in the temple. Even so, the consecration of the temple and the Forum were long delayed. The Forum was very much a familial military monument.
The Forum opened with a lavish set of games. These were presided over by Gaius and Lucius. An aristocratic display of arms by the youths of Rome (the Trojan games) took place. Two hundred and sixty lions were hunted in the circus. A spectacular reenactment of the sea battle of Salamis was staged. The original conflict had been between Persians and Athenians and this time as well the Athenians won. It seems likely that Augustus intended people to think of the Romans as inheritors of the Athenian role and the Parthians as the contemporary representatives of the Persians.
Thirty-six crocodiles were also hunted. The crocodile was the symbol of Egypt and it seems likely that Augustus meant to reference his conquest of Egypt.
The Roman senate and people responded by inventing a new title for Augustus. Suetonius (Augustus 58) says that there was a spontaneous popular demonstration in which the people offered Augustus the title Pater Patriae (Father of the Nation). A delegation was sent to Augustus, who was at Antium on the coast. He refused the honour. But when he was next in the theatre, the crowd offered the title again. The request was supported in a meeting of the senate by Valerius Messala, and a tearful Augustus accepted the honour in recognition of the universal regard with which he was held.
Although moderns have a tendency to see such titles as empty flattery, the title was meaningful for Augustus. In the concluding chapter of the Res Gestae (35) Augustus turns to this title as a summation of his career. The title was inscribed on his house, in the senate house, and on a status of Augustus in a four-horse chariot that the senate had voted for him in the Forum of Augustus. It figures heavily on the later coinage as well.
As the universal father, Augustus may not have acquired more power, but paternal authority was a powerful moral influence in Roman society. Its prominence fits with one of the messages of the Res Gestae: that Augustus ruled not through magisterial or constitutional power, but through the force of his personality and the regard with which he was held by all the Roman people.
There was an association between the dedication of the Temple, the award of the title and the increasing eminence of Gaius and Lucius, his grandsons and adopted sons. The dynasty seemed now safe and the succession assured.
Gaius was immediately sent to the Danubian provinces in order to gain military experience. But there was then news of trouble with Parthia. Augustus reacted by appointing Gaius to command in the East. There are parallels here. Augustus’s own authority had been enhanced by campaigns in 20 BC and he had been aided in those campaigns by the young Tiberius. In the longer term, Julius Caesar and Mark Antony had also sought to assert their political authority with Eastern campaigns and the sending of a young prince to the East would inevitably have drawn comparisons with Alexander the Great (Dio, 55.10). His arrival was such that even Tiberius felt it necessary to stir himself and head to Chios to meet the youth whom everyone regarded as his replacement.
His younger brother was sent to Gaul and even the very young Agrippa Postumus began to appear in public.
Relations between Tiberius and the two young men were poor. There were stories that Marcus Lollius, who was a leading general and adviser to Gaius was saying hostile things. Some centurions in Gaius’s army were accused of being connected to Tiberius and there were rumours that he was planning an assassination of the youth. Perhaps in response, one of Gaius’s circle offered to kill Tiberius, but as yet the Augustan family had not resorted to murdering each other. In Gaul, statues of Tiberius were overthrown, presumably with at least the passive support of Lucius, a sign that he was no longer regarded as part of the imperial family (Suetonius, Tiberius 11-13).
Then, disaster struck. Julia had already been exiled in 2 BC for what seems to have been a sex scandal. Gaius was struck by a spear during a siege. It did not immediately kill him, but the wound became infected. The illness was prolonged sufficiently for Gaius to write to Augustus and beg to be relieved of his duties. Augustus agreed but summoned him back to Rome. Gaius died on the journey. Lucius was already dead of a fever. Inevitably, their deaths have led to conspiracy theories: they benefited Tiberius. But medical care in the Roman world was very primitive and people died at young ages (Dio, 55.10a).
Tiberius was already back in Rome, having returned to the city perhaps in part to be away from Gaius. Augustus needed him. He became once again heir presumptive.
Gaius and Lucius represented a model of imperial power that was monarchic. Their claim to power was their descent. They behaved like princes. Their mother can be seen as an imperial princess. With the return to Tiberius, the Republican model won out. Tiberius could be seen as the most experienced man for the job. But the reversion was not through choice. It was through the accidents of survival.