No proper name, but a mere title given to Octavian, because he was head of the priesthood. In the reign of Diocletian the two emperors were each styled Augustus (sacred majesty), and the two viceroys Cæsar. Prior to that time Hadrian limited the title of Cæsar to the heir presumptive.
Sigismund II of Poland. (1520, 1548–1572.)
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894