section_path: Historiography/Primary and secondary sources
section_name: Primary and secondary sources
paragraph_text: Primary and secondary sources
  
  The two longest ancient accounts of the Roman history, the histories of Livy and Dionysius of Halicarnassus, were composed 500 years later than the date for the founding of the republic and 200 years from the defeat of Hannibal. Although there has been a diversity of works on ancient Roman history, many of them are lost. As a result of this loss, there are gaps in Roman history, which are filled by unreliable works, such as the Historia Augusta and other books from obscure authors. Historians used their works for the lauding of Roman culture and customs, and to flatter their patrons. Caesar wrote his own accounts of his military campaigns in Gaul and during the Civil War in part to impress his contemporaries.
  
  In the Empire, the biographies of famous men and early emperors flourished, examples being The Twelve Caesars of Suetonius, and Plutarch's Parallel Lives. Other major works of Imperial times were that of Livy and Tacitus.
  
  Interest in studying, and idealising, ancient Rome became prevalent during the Italian Renaissance. Edward Gibbon's The History of the Decline and Fall of the Roman Empire "began the modern study of Roman history in the English-speaking world". Barthold Georg Niebuhr was a founder of the examination of ancient Roman history and wrote The Roman History, tracing the period until the First Punic war. During the Napoleonic, The History of Romans by Victor Duruy highlighted the Caesarean period popular at the time. History of Rome, Roman constitutional law and Corpus Inscriptionum Latinarum, all by Theodor Mommsen, became milestones.