Interesting comparison. From the Wikipedia [1]:

> For the early part of his reign, he is said to have been "good, generous, fair and community-spirited", but increasingly self-indulgent, cruel, sadistic, extravagant, and sexually perverted thereafter, an insane, murderous tyrant who demanded and received worship as a living god, humiliated the Senate, and planned to make his horse a consul. [...]

> During his brief reign, Caligula worked to increase the unconstrained personal power of the emperor, as opposed to countervailing powers within the principate. [...]

> He had to abandon an attempted invasion of Britain, and the installation of his statue in the Temple in Jerusalem.

[1] https://en.wikipedia.org/wiki/Caligula

I, Claudius does a solid fictionalization of the man. (Suetonius if you’re craving drier.)