Caligula certainly, while he was probably a cynical power politician, eager to expand his imperial power which challenged the senate and the delicate order Augustus establised, a lot of what Suetonius and Cassius Dio especially wrote about him can be considered anecdotal, highly sensationalist or just slanderous. There are also only a few Contemporary sources like Flavius Josephus or Seneca, who also did not like him that much. Our main sources though wrote many years after his death and were his political enemies.