The historical sources
The problem of sources in the case of the emperor Caligula, is a complex issue. The Lives of the Caesars by Suetonius is the main script where you can get information on his reign. However, as well as other documents handed down to us (such as the writings of Dio Cassius Cocceio), the writings of Suetonius tend to focus on anecdotes about the supposed cruelty and mental instability of Caligula, and some modern historians have expressed doubts about the reliability of these reports (Suetonius devotes nine chapters of his biography in Prince Caligula Caligula and 39 monster).
It was certainly a character discussed, very popular among the Roman people but against the political class and the class from which they came to historians. Unfortunately it is not come down to us on the part of Caligula Annals of Tacitus, the historian of the period generally considered more rigorous.
The most important news to the appearance of Caligula comes from Suetonius. It appears that came to six feet tall, he was almost bald (at least in the last years of his reign), and that his eyes were sunken and insightful. It was a great charioteer (driver of chariots), with an agile and physically.
Caligula ('little murky, "the shoes of the legionaries, affectionate nickname given to him at a young age by the soldiers of his father Germanicus) was the third son of Germanicus and Agrippina Major, general much loved by the Roman people. His father was the son of Drusus major (brother of Tiberius and son of Livia, wife of Augustus) and Antonia Minor (daughter of Mark Antony and Octavia, sister of Augustus). The mother was the daughter of Marcus Agrippa Vipsanio (friend of Augustus) and Julia (daughter of first marriage of Augustus).
Also his father Germanicus was adopted by Tiberius, which was adopted by Augustus, who in turn was adopted by Julius Caesar.
This particular family situation (which could go up by Augustus Caesar, and then even to the very origins of Rome, Aeneas and Venus) made Caligula, the most likely successor to Tiberius.
As a boy accompanied his parents on military expeditions in Germany (14 - 16) and wore the shoes in the fields of legionnaires (Caliga), hence the affectionate nickname "Caligula", given to him by the soldiers.
In the 17th, after witnessing the triumph of his father in Rome, share with family in the wake of Germany sent on a mission to East. Only two years later his father died, and Caligula, with her mother, he returned to Italy.
The hypothesis advanced by some to Caligula in seven years had been guilty of the death of his father in Syria is not supported by historical sources.
In 27 will live at home paternal great-grandfather of Livia on the Palatine Hill and 29 at the home of her grandmother Antonia Minor where he will meet the three young princes Thracians, Polemon II (which will give the kingdom of Pontus and the Bosporus), Rhoimetalkes (which give half of the ancient kingdom of Thrace) and Kotys III (which will give the Lesser Armenia).
The emperor Tiberius retired to Capri in 26 already, he wants to Caligula in 31, when it became Pontifex (priest). In 33 he became superintendent, and here you close the cursus honorum of Caligula.
Tiberius nevertheless appoint his successors in his will (35) Twin Caligula and Tiberius.
He had four wives: Junia Claudilla, Livia Orestilla, Lollia Paulina, already married to Publius Memmius Caesonia Regulus and Milo, who bore him a daughter named Julia Drusilla in honor of her sister died
Accession to the throne
After the death of Tiberius, which occurred March 16 to 37, the Senate will stop the test, leaving the leadership of the Empire to Tiberius and Caligula Twin, nephew of the late emperor, saying that as of this writing Tiberius was insane and declared Caligula Imperator 18 March 37. Caligula came to power with the support of all: the Senate, army and people. The reasons for this approval are different: his young age (25 years coming), the popularity of his father, the length of the reign of Tiberius (23 years), childhood spent in the camps, the misfortune of his family, relationship with both Mark Antony and Augustus, with his devotion to family.
The principality (37-41)
It was thought that Caligula would have continued the policy of his father, Germanicus, but it did not. The short reign of Caligula was characterized by a series of massacres against domestic opponents and from acts that tended to a constant humiliation of the senatorial class. Caligula was acting very strange ways that identified him as a "crazy". Ancient sources saw him as an example of "bloody madness". According to legend, in fact, the senator named his horse (named Incitatus), although it is clear that its decree appointing expressed his utter contempt for the Senate might well have been enriched by his beast. In fact only a joke Caligula once said that he could appoint his horse as a senator, this being more capable of the senators themselves.
Other stories show that he had frequent bouts of anger. Tacitus recounts that during a banquet, Caligula suddenly burst out laughing. A diner who was sitting with him asked him why he laughed and said that Caligula was thinking that the latter's death after he killed. Caligula adopted a policy of monarchical absolutism, he wanted to become a sovereign divine honors which made the model of oriental monarchies, exhausting the known process of deification of dead emperors. Caligula became autocratic attitudes and demanded that a temple was erected. He became popular with expensive gifts to the populace and circus games.
If the emperors before him had opted, at least in the western part of the empire, to maintain ties with the republican tradition of Roman power, he veered dramatically to the east, towards a form of absolute power at that time still unknown in Italy, anticipating thus become a major trend among the Roman emperors from the third century of our era.
The new emperor, to avoid problems dynastic named Tiberius Twin princeps iuventutis and adopted him, naming him his heir. To avoid, however, that Tiberius Twin claim that it was co-regent, 38 had him killed or led him to suicide. The same fate befell the praetorian prefect Macro. Caligula probably did not trust some people more than they could, with their power, money or charisma, delete it. More than cruelty in this case, we can talk about Machiavellian politics of this young man.
According to sources, Caligula, at the height of his reign, he wanted to be God could be proclaimed the umpteenth manifestation of his madness, or a subtle policy to increase its power in the Hellenistic peoples, long accustomed to consider their sovereign deity. In short, the attempt of a religious young prince to keep power by all means. This, however, caused much discontent, especially in populations that already had problems with the simple civil authority of Rome, not to mention the religious one, for example the Jews, which triggered heavy movements of revolt
Contemporary explanation of the Emperor's New Groove
Recent studies trace the strange events of Caligula and other emperors, like lead poisoning, which in technical terms is called lead poisoning. Lead poisoning is caused by Caligula's ancient Roman custom of drinking wine, holding it slightly softened skins of lead. With respect to Roman pipes of lead, which is mentioned in some articles, do not cause lead poisoning, because the water formed a thin layer of oxide of lead white, insoluble in water, while the slight acidity of this wine was dissolved salt, that is just sweet.
Economic and financial management
On the death of Tiberius in the coffers of the Roman fiscus were 2,700,000,000 sesterces  Caligula expenses in a year or so. Some of the costs incurred by the new emperor were inevitable: the various gifts to the people, the army, the Praetorian Guard (to which he gave a donation twice that promised by Tiberius, 2000 sesterces a head ) and the vassal kingdoms of Rome ( 100,000,000 sesterces to those of Antiochus IV of Commagene). Do not forget also that respected the will of Tiberius, Caligula, although it was formally annulled by the Senate, and gave the set at all. Should not forget the huge banquets and various organizations to keep calm and good people. All this is added, however, other extravagances, cited by contemporary historians, as the stable of his horse all in ivory and marble, the 2 million sesterces donated to a charioteer and a million donated to Livio Gemini (who swore they saw Drusilla ascend into heaven, and converse with the gods). It should also be mentioned the abolition of tax on sales.
And to improve the economic situation Caligula, like many later emperors, expropriated the assets of many senators, accusing them of plotting against him (not always a false accusation).
Modern historians tend to discount the voices that speak of a critical financial state coffers, as presented by the ancient sources, since it does not explain either the decrease of tax burden took place under his rule, nor one that occurred under his immediate successor.
Several acts were interesting features of this emperor, the abolition, in the first year of government, the law of treason, an act much hated by the senators, however, reintroduced in 39. Also interesting is the project implemented in 38 of the elections and return to the courts, at least formally, the ancient prerogatives, with the direct consequence that the people elect the magistrates. In general we can divide the judicial policy of this emperor in two periods, the first very liberal, pro-People, in which it sought an agreement with the senators and the second in which the princeps did everything to maintain power.
With the reigns allies did not follow the same policy, was based a lot on the sympathy and trust that each ruler was able to convey. Exiled Mithridates, king of Armenia, and sent to death Ptolemy, king of Mauritania, and reduced his kingdom to province, appointed king of Commagene, a region reduced to a province in 18, Antiochus IV, who gave 100 million sesterces.
Kingdoms also gave the three young princes Thracians who had met in his youth, to grandmother's house Antonia: a Polemon II will give the kingdom of Pontus and the Bosporus in 38 to Rhoimetalkes half of the ancient kingdom of Thrace and the Kotys Armenia Minor.
He helped in every way Herod Agrippa, who entrusted to him, at first, the north-western Palestine, which after the death of Herod Philip II (34) was under the direct control of Rome, later also the territories of the tetrarch of Galilee, Herod Antipas, who was accused of wanting to seize the territories of Herod Agrippa, who will be exiled and then eliminated in the first 40.
Caligula had important ancestors who had earned the glory of war with business, it is likely, therefore, it was determined to emulate their deeds and in the case to overcome them. If more Drusus and Germanicus had focused on Germany, he had to overcome their deeds, not only to gain the same region, but crossed the ocean to arrive in Britain. It would have been the first emperor Augustus after the campaigns in Spain in 26-25 BC to lead an army into battle.
According to Suetonius he did levers throughout the empire and amassed a large quantity of food. According to Dio Cassius, he enlisted for his exploits between 200 and 250 000 men. In 39 Caligula suppressed a revolt among his troops and marched towards the Rhine in the high northern coast of Gaul, apparently intending to invade Britain. Instead, he ordered the troops to get in the water looking for shells, as Suetonius tells us, or more probably gave up a shipment badly prepared.
Caligula was assassinated in a conspiracy led by two Praetorian tribunes, Cornelius Sabinus and Cassius Cherea, January 24 to 41. With him died his wife Miloni Caesonia and their baby daughter, Julia Drusilla (named in memory of the sister of Caligula he deified his death) that was brutally crushed against a wall. He was succeeded by his uncle Claudius, who, reportedly has been hiding behind a curtain.