Imperator Gaius Julius Caesar Augustus reigned from 23 September 63 BC to 19 August AD 14. He ruled alone from 27 BC until his death in 14 AD. Born Gaius Octavius Thurinus, he was adopted posthumously by his great-uncle Gaius Julius Caesar in 44 BC. In 27 BC he was awared the honorific title Augustus (= "the revered one") by the Roman Senate, and consequently was called Gaius Julius Caesar Augustus. Commonly he is called Octavius, referring to events between 63 and 44 BC, or Octavian, referring to events between 44 and 27 BC, and Augustus when referring to events after 27 BC. Both his adoptive surname, Caesar, and his title Augustus became the permanent titles of the rulers of Roman Empire for fourteen centuries after his death, in use both at (Old) Rome and at New Rome, Constantinople. In many languages, Caesar became the word for Emperor, as in the German Kaiser and in the Bulgarian and subsequently Russian Tsar. The cult of Divus Augustus continued partly 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.