Augustus
Augustus' reign laid the foundations of a regime that lasted, in one form or another, for nearly fifteen hundred years through the ultimate decline of the Western Roman Empire and until the Fall of Constantinople in 1453. Both his adoptive surname, Caesar, and his title "Augustus" became the permanent titles of the rulers of the Roman Empire for fourteen centuries after his death, in use both at Old Rome and at New Rome. In many languages, "Caesar" became the word for "Emperor", as in the German "Kaiser" and in the Bulgarian and subsequently Russian "Tsar" (sometimes Csar or Czar). The cult of "Divus Augustus" continued until the state religion of the Empire was changed to Christianity in 391 by Theodosius I. Consequently, there are many excellent statues and busts of the first emperor. He had composed an account of his achievements, the "Res Gestae Divi Augusti", to be inscribed in bronze in front of his mausoleum. Copies of the text were inscribed throughout the Empire upon his death. The inscriptions in Latin featured translations in Greek beside it, and were inscribed on many public edifices, such as the temple in Ankara dubbed the "Monumentum Ancyranum", called the "queen of inscriptions" by historian Theodor Mommsen.
Death of Cleopatra
The deaths of Cleopatra and Caesarion marked the end of both the Ptolemaic dynasty's rule of Egypt and the Hellenistic period, which had lasted since the reign of Alexander the Great (r. 336–323 BC). Egypt became a province of the newly established Roman Empire, with Octavian renamed in 27 BC as Augustus, the first Roman emperor, ruling with the facade of a Roman Republic. Roller affirms that Caesarion's alleged reign was "essentially a fiction" invented by chroniclers of Egypt, such as Clement of Alexandria in his "Stromata", to explain the gap between Cleopatra's death and the induction of Egypt as a Roman province directly ruled by Octavian as pharaoh of Egypt. Antony's three children with Cleopatra were spared and sent to Rome; their daughter Cleopatra Selene II eventually married Juba II of Mauretania.