Caesar (カエサル, Kaesaru) appears in the Persona games as Akihiko Sanada's Ultimate Persona.
The title of Caesar is bestowed upon the rulers of Imperial Rome. It is derived from the family name of Julius Caesar, who effectively transformed the Roman Republic into an Empire. He is one of the few personas in the series that is based on an actual person rather than a mythological figure (Julius Caesar was deified by the Roman Empire however and was supposedly killed by Brutus and replaced by his adopted son Octavian, later known as the Emperor Augustus).
Like Akihiko Sanada's initial persona, Polydeuces was a great warrior who eventually ascended to become a god upon his death much like Caesar. This explains his appearance, as it seems to be a mix of the colors of Castor and Polydeuces blended together. As "ruler of the world" as Augustus was known for, that explains the globe he carries in his hand. The little man inside of Caesar's chest is a reference to how much Akihiko admired and looked up to Shinjiro. Even after his demise, many people still viewed him as insignificant, but to Akihiko, he meant the whole world to him, and made the biggest influence in Akihiko's life.
- The classical Latin pronunciation of the name is (kae-sar), emphasizing the diphthong "Æ". In the English version of Persona 3, Akihiko's pronunciation when he summons this Persona softens the diphthong and is pronounced as (see-zer), its Anglicized variant.
- The little man's red mask inside of Caesar bears a striking resemblance to Castor's own mask.