Gaius Caesar

Gaius Caesar (20 BC – 21 February 4 AD) was a grandson and heir to the throne of Roman emperor Augustus, alongside his younger brother Lucius Caesar. Although he was born to Marcus Vipsanius Agrippa and Julia, Augustus' only daughter, Gaius and Lucius were raised by their grandfather as his adopted sons and joint-heirs. He experienced an accelerated political career befitting a member of the Julio-Claudian dynasty, with the Roman Senate allowing him to advance his career without first holding a quaestorship or praetorship, offices that ordinary senators were required to hold as part of the cursus honorum.

In 1 BC, Gaius was given command of the eastern provinces, after which he concluded a peace treaty with King Phraates V of Parthia on an island in the Euphrates. Shortly afterwards, he was appointed to the office of consul for the following year, 1 AD. The year after Gaius' consulship, Lucius died at Massilia in the month of August. Approximately eighteen months later, Gaius died of an illness in Lycia. He was married to his second cousin Livilla but they did not have children. In 4 AD, following the deaths of Gaius and Lucius, Augustus adopted his stepson, Tiberius, as well as his sole-surviving grandson, Agrippa Postumus.

Marcus Vipsanius Agrippa was an early supporter of Augustus (then "Octavius") during the Final War of the Roman Republic that ensued as a result of the assassination of Julius Caesar in 44 BC. He was a key general in Augustus' armies, commanding troops in pivotal battles against Mark Antony and Sextus Pompeius. From early on, Agrippa was trusted to handle affairs in the eastern provinces and was even given the signet ring of Augustus, who was seemingly on his deathbed in 23 BC, a sign that he would become princeps were Augustus to die. However, as soon as he recovered, Augustus began to show he favored his nephew, Marcus Claudius Marcellus, then just 19. However, Marcellus died of an illness that had spread throughout the city of Rome that year.

With Marcellus gone, Augustus arranged for the marriage of Agrippa to his daughter Julia the Elder, who was previously the wife of Marcellus. Agrippa was given tribunicia potestas ("the tribunician power") in 18 BC, a power that Augustus received in 23 BC, and later on was exercised only by the emperor and shared with some heirs (Agrippa, Tiberius). The tribunician power allowed him to control the Senate. Agrippa acted as tribune in the Senate to pass important legislation and, though he lacked some of the emperor's power and authority, he was approaching the position of co-regent.

Gaius was born in Rome in 20 BC to Marcus Vipsanius Agrippa and Julia the Elder. He was a part of the Julio-Claudian dynasty, and was related to all the Julio-Claudian emperors. On his mother's side, he was the oldest grandson of emperor Augustus. He was the stepson of Tiberius by his mother Julia's marriage to him, and brother in law of Claudius by his sister Agrippina the Elder's marriage to Germanicus. He also was the uncle of Caligula, who was the son of his sister Agrippina. The last emperor of the dynasty was Nero, who was Gaius' great-nephew and the grandson of Germanicus. An annual sacrifice on his birthday was granted in a decree.

In 17 BC, his brother Lucius was born. Augustus immediately adopted both Gaius and Lucius from their father by a symbolic sale, and named both Gaius and Lucius his (personal) heirs. It is unknown what their father thought of the adoption. Their adoptive father initiated them into administrative life when they were still young, and sent them to the provinces as consuls-elect. Augustus taught Gaius and Lucius how to read, swim, and the other elements of education, taking special pains to train them to imitate his own handwriting, mostly by himself. Shortly after their adoption in the summer, Augustus held the fifth-ever Ludi Saeculares ("Secular Games"). The adoption of the boys coupled with the games served to introduce a new era of peace – the Pax Augusta.

That year his family left for the province of Syria, because Agrippa was given command of the eastern provinces with proconsular imperium maius. Four years later, in 13 BC, Gaius took part in the Trojan games with the other patrician youths at the dedication of the Theatre of Marcellus. Also in 13 BC, Agrippa and Augustus returned to Rome. Augustus sent Agrippa to Pannonia at the end of 13 to suppress a rebellion. Agrippa arrived there that winter (in 12 BC), but the Pannonians gave up their plans. Agrippa returned to Campania in Italy, where he fell ill and died soon after. The death of Gaius' father made succession a pressing issue. The aurei and denarii issued in 13–12 BC made clear the Emperor's dynastic plans for Gaius and Lucius.

The luxurious rural villa-estate at Ossaia near Cortona was owned by Gaius and Lucius Caesar.