Gaius Caesar, son of the popular general and dynastic heir, Germanicus, and great grand-son of Augustus through his mother, was born AD 12 shortly before the death of Augustus. Evidence for the life of the 3rd Roman emperor is sparse, as the work of Tacitus for this period is lost. What does exist, primarily Suetonius, Seneca, Cassius Dio, Josephus and Philo, is completely negative and openly hostile for a variety of reasons. While these accounts are certainly somewhat tainted by the personal and political agendas of the authors, there is a basis for truth in each. The life of Gaius is clouded in 'madness' and 'megalomania', and there is enough evidence to back up claims of adverse behavior whether caused by mental illness, personal ego, or even historical embellishment. Despite his youth, his short reign of less than 4 years, and the slanderous history that followed, certainly indicates a widespread dislike. Had some of the rumors of depravity, indiscretion and megalomania not been true, and thus his assassination purely the result of political maneuvering, than at least some small contrary record might be expected to be found. All ancient sources, however, paint Gaius with a fairly similar brush.
Caligula, as Gaius is commonly known, received the nickname while on campaign with his father in Germania. As a baby and young boy he was often dressed in a mock legionary uniform, including the sandals called caligae, much to the delight of the soldiers. The men soon began to refer to their new mascot as Caligula, or little sandals. Despite this early pleasantry, however, Caligula lived a harsh youth, where instability within the imperial family caused paranoia and open suspicion. After the death of his father in AD 19, a rift formed between members of the Julio-Claudian house pitting his surviving family members against the reigning emperor Tiberius. His mother and 2 brothers eventually suffered horrible fates under the terror of Sejanus, but Caligula managed to avoid their fates. First placed under the care of his great-grandmother Livia, then grandmother Antonia, Caligula and his sisters survived, likely developing a bond that would later lead to accusations of all sort of incest and perversity. Shortly prior to the fall of Sejanus in 31 AD, and amidst fear for the continuation of the dynastic line, Caligula was brought to live with Tiberius on the island of Capri. Here he remained, holding only an honorary Quaestorship in AD 33, likely learning little to nothing of how to rule an empire, until Tiberius death in AD 37. There has been some speculation that Caligula was involved in the death of Tiberius, having him smothered to allow his own ascension, but the theory seems implausible. Tiberius was 77 years old at the time and likely in poor health anyway, but the story added fuel to the ancient fire regarding Caligula's madness.
'Gaius' was initially welcomed with great joy by both the masses and the Senate. Macro, the Praetorian Prefect, immediately propped Caligula up as the new princpeps, and with their support there would be little challenge to his authority. Being the son of the once revered Germanicus also brought the support of the Legions, an all important factor to consider in imperial politics. Despite the fact that Tiberius' will had named him joint heir with his cousin, 18 year old Tiberius Gemellus, the Senate revoked this provision (certainly by Caligula's intervention), paving the way for single rule by Caligula. To be sure to avoid future questions regarding the principate and succession, Tiberius Gemellus 'died' within a few months of Caligula's accession to power.
Initially, the young Emperor's rule was very promising. A speech before the Senate assured them of co-operative governing with the new 'administration'. He took it upon himself to destroy many records from the Tiberius treason trials. In this he not only cleared his mother and other relatives but certainly allowed many of Rome's elite to breathe a huge sigh of relief. The treason trials had come to an end and the dark rule of Tiberius was followed with a new hope. Generous bequests were paid to the people of Rome and especially to the Praetorians. Exiled citizens were recalled and others who had had properties confiscated were reimbursed. He did propose the deification of Tiberius, but this act was widely opposed. Rather than push through the unpopular act, Caligula let it drop, but the laws and deeds of Tiberius were allowed to stand for posterity purposes. He made another wildly popular gesture of piety by sailing to the islands where his mother Agrippina and brother Nero were killed, retrieving their ashes for the mausoleum of Augustus.
His popularity, along with the now defined tradition of Imperial rule, granted him freedom of governing not known by either of his predecessors. While Augustus certainly held ultimate power, his political career was one of cunning and systematic creation of a new system. Tiberius, following in the footsteps of Augustus, enjoyed his own freedom to rule, but had to deal with legionary revolts resulting from successions and was generally despised. Caligula, on the other hand, had the deepest admiration of the Roman world, and faced little political adversity. Perhaps this coddled political part of his life, coupled with a terribly tragic youth filled with murder and family intrigue, would lead the promising young man down a much darker path.