Third son of Germanicus  (nephew of Emperor Tiberius) and Agrippina, Gaius Caesar Germanicus was born in Antium in the year 12 AD. -
While staying with his parents at the German border, as a small child he used to wear a miniature version of the military sandals (caligae) - causing the soldiers to start calling him Caligula  (little sandal); a nickname that stayed with him all his life.

During his late teens, his mother and brothers were arrested and killed, victims of the plotting praetorian prefect Sejanus, who thought had a chance at
succession; Gaius to be his next planned target -  but Tiberius heard about the conspiracy and ordered Sejanus arrested and executed.
The island of Capri became Caligula's home, living in the Emperor's luxurious residence; and was appointed joint heir with Tiberius Gemellus.  At the time, Tiberius was an old man of 77 and Gemellus was a child, so it was obvious that Caligula would inherit the throne in a not so distant future.
He was named quaestor in 33 AD, but was not given any administrative training.

At Tiberius' death, with the support of Macro, commander of the praetoians,Caligula was immediately hailed as Princeps (first citizen) by the senate.
On his return to Rome, the senate bestowed upon him all the powers of the Imperial Office - Caligula declaring Tiberius will invalid; the child Gemellus
not granted his claim to the joint reign.-  It was the Army, specially, that very loyal to the House of Germanicus, sought to see Caligula as sole ruler.
He abolished Tiberius gruesome treason trials, paid generous bequests to the people of Rome and a handsome bonus to the praetorian guard; becoming extremelly popular thrughout the Empire.

In October of 37AD Caligula fell seriously ill, causing great concern among his subjects. When he recuperated,  he was no longer the same man, and Rome soon found itself living a nightmare.
According to historian Suetonius, Caligula suffered from epilepsy; and this or some other cause,
violently affected his mental state and became totally irrational; with illusions not only of grandeur but also of divinity.- Caligula now suffered a chronic inabiliy to sleep, managing only a few, nightmare filled hours a night.

Caligula had four wives, three of them during his reign. It was said he committed incest with each of his three sisters.

in 38AD, Caligula put to death without a trial, his principal supporter - the praetorian prefect Marco. The young Timerius Gemellus suffered the same fate
shortly afterwards.- The father of Caligula's first wife was compelled to commit suicide as Caligula became more unbalanced. To pay for his  unbound excesses, he introduced heavy taxation, created a new tax for prostitutes and opened a brothel in a wing of the Imperial Palace.
The senate was alarmed by all these occurrences. There was no doubt now, that the Emperor was a dangerous madman.
Confirming their worst fears, Caligula announced the revival of the bloodthirsty treason trials, cause for serious terror in the latter years of Tiberius reign.

His favorite race horse "Incitatus" was kept in a stable of carved ivory inside the palace. The horse was often invited to dine with the Emperor and his guests, and Caligula seriously considered making the horse consul.
Rumors of disloyaty began to reach an ever more deranged Emperor. A recently retired governor was forced to commit suicide.

It was no surprise that at least three conspiracies were launched against his life, but foiled.- When it became evident that the Emperor suspected that the joint
praetorian prefects were planning his assassination, it prompted them in order to prevent their execution, to join some seators n a plot.

On January 24, 41AD, Cassius Chaerea, with two military colleagues fell upon the Emperor in a corridor of his palace. Several praetoreans then swept through the palace seeking to kill any surviving relatives. Caligula's fourth wife was stabbed to death, and her baby daughter's skull was smashed  against a wall.- The scene was gruesome, butit freed Romans from the insane rule of a tyranr.

Caligula had been Emperor for less than four years.