Private Collection, Newport, Rhode Island
To restore a marble bust, we begin with historical research:
Caesar Augustus (23 September 63 BC – 19 August 14 AD) was the founder of the Roman Empire and its first Emperor. He, Mark Antony, and Marcus Lepidus formed the Second Triumvirate to defeat the assassins of Caesar. Following their victory at Philippi, the Triumvirate divided the Roman Republic among themselves and ruled as military dictators.[note 4] The Triumvirate was eventually torn apart under the competing ambitions of its members.
After the demise of the Second Triumvirate, Augustus restored the outward facade of the free Republic, with governmental power vested in the Roman Senate, the executive magistrates, and the legislative assemblies. In reality, however, he retained his autocratic power over the Republic as a military dictator. By law, Augustus held a collection of powers granted to him for life by the Senate, including supreme military command, and those of tribune and censor. It took several years for Augustus to develop the framework within which a formally republican state could be led under his sole rule. He rejected monarchical titles, and instead called himself Princeps Civitatis (“First Citizen of the State”). The resulting constitutional framework became known as the Principate, the first phase of the Roman Empire. Augustus dramatically enlarged the Empire, annexing Egypt, Dalmatia, Pannonia, Noricum, and Raetia; expanding possessions in Africa; expanding into Germania; and completing the conquest of Hispania.
The historical information on Caesar Augustus is abridged from https://en.wikipedia.org/wiki/Augustus.