Caligula’s Descent into Madness

40 CE: Caligula announced his self-deification, building temples and erecting statues, even in Rome, to his glorified self. He even ordered that a statue of himself should be placed in the Temple of Jerusalem and the Jews be forced to worship him (the procurator wisely postponed executing this order, and it had not yet been carried out when Caligula was assassinated). This deification was part of Caligula’s apparently systematic concept of imperial power, of what he liked to term his “inflexibility” (called by Robert Graves his “immovable rigor”). Was Caligula clinically insane? Was he the evil monster portrayed by Robert Graves? The ancient sources are uniformly hostile, and modern historians differ in their interpretations of his behavior.
— Read on www.vroma.org/~bmcmanus/caligula.html