Caesar
From Tardis Wiki, the free Doctor Who reference
Caesar was a title held by the ruler of the Roman Empire. Nero, (DW: The Romans) Augustus and Tiberius were known Caesars. Jesus Christ was executed during the 21st year of Tiberius' reign. (PDA: Byzantium!)
In an alternate timeline, Caesar was a title held by Holy Roman Emperor Winston Churchill. (DW: The Wedding of River Song)