Gaius Caesar

Statue of a Julio-Claudian prince. The head probably depicts Gaius Caesar, made 5 BC-14 AD. Altes Museum, Berlin

Following the death of King Herod of Judaea in 4 BC,[23] his sons Antipas and Archelaus both came to Rome with their own copy of Herod's will to plead their case as to why they each deserved to inherit their father's kingdom. Augustus, as usual, declined the sole responsibility of decision. He convened a council of senators, among whom he included Gaius. The council decided to ratify the will brought by Archelaus, which included a large bequest to Augustus and his wife Livia.[24][25]

The cities of Judaea rose in revolt after the procurator, Sabinus, garrisoned Syria Palaestina to guard the tens of millions of sesterces promised to the Emperor.[26] The governor of Syria, Varus, was forced to bring in the legions from Syria to restore order.[25]

At the same time, King Phraates IV of Parthia had seized Armenia with the help of Armenian nationalists, and expelled Tigranes IV, the king installed by Rome.[27] Historian Ferrero speculates that Phraates may have been hoping to use Armenia as a bargaining chip to secure the release of his sons who were held captive by the Romans. Roman supremacy in Asia depended on its possession of Armenia as a protectorate. Before Rome could deal with the Parthians in Armenia, it would first need to make its Syrian legions available, which were still tied down in Palestine.[28]

In order to free up the legions there, the Kingdom of Judaea was divided among the sons of Herod the Great. One half remained under Archelaus, while the other half was subdivided between his brothers, Antipas and Philip. This served to restore stability to the region, whilst keeping Judaea from becoming powerful. Having settled matters in Judaea, the Emperor decided to deploy an army to Armenia to re-establish its status as a Roman protectorate and to show the eastern world that Rome held dominion over all land as far as the Euphrates.[28]

Remains of the Forum of Augustus with the Temple of Mars Ultor.

Due to his advanced age, Augustus was unable to travel to the east himself. There were few the Emperor trusted to settle matters in the east, but he was confident Gaius could. Gaius made a good choice, because his presence represented that of the imperial family – all orders, promises, or threats coming from him were as valid as if they came from the Emperor himself. Nonetheless, he was only eighteen, and therefore too young for the conduct of important business.[29]

Before leaving for the east, he and his brother Lucius were given the authority to consecrate buildings, and they did, with their management of the games held to celebrate the dedication of the Temple of Mars Ultor (1 August 2 BC). His youngest brother, Postumus, participated in the Trojan game with the rest of the equestrian youth. 260 lions were slaughtered in the Circus Maximus, there was gladiatorial combat, a naval battle between the "Persians" and the "Athenians", and 36 crocodiles were slaughtered in the Circus Flaminius.[note 1][30]

Friends of Augustus had hoped that he would abandon his plan of sending Gaius to the east but, faced with the troubles in the east, he persisted with the plan and dispatched Gaius to Syria at the beginning of 1 BC. The Emperor entrusted Gaius with proconsular authority and had his second cousin, Livilla, marry him. Livilla was the daughter of Drusus the Elder and Antonia Minor.[30][31]

Due to his youth and inexperience, the Emperor had others go with him as advisors. Among his entourage to the east were: Marcus Lollius as adiutor ("helper"),[32] Publius Sulpicius Quirinus as rector ("guide"),[33] the future historian Velleius Paterculus,[34] Lucius Domitius Ahenobarbus (grandfather of Nero),[35] Juba II of Numidia,[36] and future praetorian prefect Sejanus.[37][38]

On his way to Syria, Gaius met with Tiberius, who had abandoned politics and retired to Rhodes.[34] According to Suetonius, Gaius gave Tiberius a cold reception on the isle of Samos. Tiberius was alienated at the meeting, by the behavior of both Lollius and Gaius' centurions. Suetonius further wrote that Tiberius wrote to the Emperor that Lollius be replaced.[32] Lollius' rivalry with Tiberius continued even after Gaius and his entourage reached Syria. Lollius strove to turn Gaius against Tiberius; Gaius, in any case, had no affection for the man who had contributed, directly or indirectly, to the ruin of his mother.[note 2] On one occasion, Lollius offered to decapitate Tiberius if Gaius gave the word.[39] Suetonius wrote that it was Lollius' growing influence that compelled Tiberius to plead with Augustus for his return to Rome.[40]

Latin inscription from the cenotaph to Gaius and Lucius Caesar in Pisa (CIL XI, 1421)

The next year, on 1 January, he entered the consulship in absentia with his brother-in-law, Lucius Aemilius Paullus, in accordance with the decision of 6 BC which named him consul designate.[19] Gaius, who was twenty, had reached Asia, and was probably at Antioch at the time his consulship commenced, where he was organizing an army for the invasion of Armenia and opening negotiations with Phraates in the hopes of securing an agreement. The Emperor did not desire an open war, and the king of Parthia seemed open to peace. Negotiations were probably hastened by the presence of Gaius' army in Syria, which threatened Parthia. From every corner the young consul was visited by envoys offering requests and paying homage. This year, monuments were raised to him and to his brother as the son of Ares or as Ares himself.[41]

His inexperience meant he was forced to rely on his companions, namely the unruly Lollius, who had taken advantage of the powers he held, and was reportedly holding towns, individuals, and even sovereign princes for ransom. After Gaius opened negotiations with Phraates, Lollius offered the Parthian king certain concessions in return for money.[42]

Preparations for the war continued into the spring and summer of 1 AD, at which point there had been a successful breakthrough in negotiations. As Phraates was not willing to go to war, he agreed to evacuate Armenia and abandon his brothers who were still in Roman captivity.[30][43] In the second half of the year,[44] Gaius had advanced with his army to the Parthian frontier to an unknown spot and brought Phraates to a final agreement on the proposals, in which he renounced all claims to Armenia and all power over his half-brothers.[45]

It was about this time that Augustus passed through Judea and commended Gaius for not offering prayers at Jerusalem, as it would have been provocative to the Jews living there.[46]

Sometime in the course of his time in the east, Gaius led an expedition into Arabia. Exactly where and for what purpose remains uncertain, though Pliny mentioned it in connection with Aelius Gallus' exploits in South Arabia.[47] The term "Arabia" is never defined, and the term was used loosely by Roman sources. Various reasons, such as an attempt by Rome to control the incense trade, have been suggested but never proven.[48] Juba II, former king of Mauretania, accompanied Gaius to the east. In order to prepare Gaius for his encounter with the Arabs, Juba wrote him a treatise. According to Pliny, the young prince made it as far as the Gulf of Aqaba. It is certain that this expedition happened before his time in Armenia, and, referencing Gaius' cenotaph in Pisa, it is almost certain to have taken place during his consulship.[36]

Author and historian John Grainger places Gaius at the Gulf of Aqaba, or in Nabataea. It is known that the Nabataean Kingdom later became the province of Arabia, and so, it might be that Gaius conducted his "Arabian expedition" to either support or to discipline the King of Nabataea, Aretas IV.[49] This is probably evidenced by the continuation of coinage in the king's name after Gaius' consulship.[36]

Cassius Dio, in a fragmentary notice,[50] mentions trouble in Egypt which was suppressed by a tribune of the Praetorian Guard. It is very likely this man was part of Gaius' entourage, but other than that nothing is known of him.[49]

Map of Armenia and the Roman client states in eastern Asia Minor.

In the year following his consulship, in spring, he had held a meeting with Phraates on the bank of the Euphrates, in which a banquet was held to celebrate a peace treaty. It was here that Phraates, offended by Lollius, disclosed the guardian's secret negotiations to Gaius. It was for the crime of extorting presents from kings (regnum muneribus) that Lollius lost the friendship of Gaius and drank poison. Pliny says he amassed a fortune from his crimes and that, as a result, his granddaughter could afford to wear jewelry worth 40,000,000 sesterces, a considerable amount of money.[42][51] The death of Lollius was fortunate to Tiberius, after which Gaius consented to his return to Rome and consequent return to Roman politics.[52]

At the same time, the throne of Armenia had become vacant and, with permission from the Emperor, Gaius placed Ariobarzanes II of Atropatene on the throne. The Romans weren't the only ones interested in Armenia: the Parthians stirred up a revolt among nationalists in the nation. A large force of rebels had occupied the fortress in the city of Artagira. Gaius was drawn into the conflict, and invaded Armenia in late August of 2 AD. He encountered no serious opposition as there were only a few revolts he had to suppress as a result of the nationalist party.[53]

On September 9, Abbadon, the leader of the rebellion, invited Gaius into the fortress to speak with him. It proved to be a trick, and Gaius was wounded in the confrontation. He had to be carried away by his outraged lieutenants. His forces promptly laid siege to the city and captured the fortress after intense fighting.[54][55] At first the wound did not seem serious and he was able to complete the pacification of Armenia, a relatively easy task.[30][56][53]

By the next year (3 AD), he was entirely prostrated by the effects of his wound, had resigned his command, and withdrawn to Syria from where he informed Augustus that he had no further desire to take part in public life.[30][53] The eastern campaign had proven severe: his health was weak and his mental balance unstable. At the age of twenty-three, the young man whom the Emperor considered his heir and sole hope of prosperity had abandoned his prospects of reputation and power in a wild fit of despair and fear. Augustus did his best to cheer him up and convince him to return to Italy. It was in vain: Gaius died in a little Lycian town on 21 February 4 AD.[57]

• Cassius Dio, Roman History Book 55, English translation
• Josephus, Antiquities of the Jews Book 17, English translation
• Suetonius, Lives of the Twelve Caesars, Life of Augustus, Latin text with English translation
• Suetonius, Lives of the Twelve Caesars, Life of Nero, Latin text with English translation
• Suetonius, Lives of the Twelve Caesars, Life of Tiberius, Latin text with English translation
• Tacitus, Annals, I–IV, English translation
• Velleius Paterculus, Roman History Book II, Latin text with English translation

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