Augustus (born Gaius Octavius; 23 September 63 BC – 19 August AD 14), also known as Octavian, was the founder of the Roman Empire and its first emperor from 27 BC until his death. Adopted heir of Julius Caesar, he emerged from the civil wars after Actium as princeps — and in Ovid's Metamorphoses he closes the poem as the greater guardian of the conquered earth while the deified Caesar watches from the sky.
Adapted from Wikipedia, "Augustus" · CC BY-SA 4.0
I.Heir, triumvir, and first emperor
Named principal heir in Caesar's will after the Ides of March 44 BC, Octavian fought for the loyalty of Caesar's veterans, formed the Second Triumvirate with Antony and Lepidus, defeated the liberators at Philippi, and finally defeated Antony and Cleopatra at Actium in 31 BC. In 27 BC the Senate granted him the title Augustus; he ruled through the principate — nominal deference to republican forms with lasting military and provincial control — until AD 14.
He annexed Egypt and other provinces, reformed taxation and the standing army, and was posthumously deified. His stepson Tiberius succeeded him.
II.Ovidian frame and atlas role
Ovid ends the Metamorphoses not on the deified dictator alone but on his heir: Augustus greater than his father, guarding the earth while Caesar's soul shines as a comet. In the atlas the id augustus is that intentional Roman reception node — parallel to julius-caesar — at the edge of Greek mythic time, not a Greek polis king.