History of the Roman Empire founder of the brief Flavian dynasty, to be followed by the Nerva–Antonine dynasty which produced the "Five Good Emperors": Nerva, Trajan, Hadrian, Antoninus Pius and the philosophically inclined Marcus Aurelius. In the view of the Greek historian Dio Cassius, a contemporary observer, the accession of the emperor Commodus in 180 AD marked the descent "from a kingdom of gold to one of rust and iron"—a famous comment which has led some historians, notably Edward Gibbon, to take Commodus' reign as the beginning of the decline of the Roman Empire. In 212, during the reign of Caracalla, Roman citizenship was granted
The Historians' History of the World of the Western Roman Empire in 476. It discusses the rise of Christianity, the many emperors who held power in Rome during the founding and the fall of the Roman Empire, the division of the Roman Empire and the many barbarian invasions (Huns, Goths, Vandals) leading up to Rome's fall. "Part XI: The History of the Later Roman Empire" states that, along with over 75 additional authors, the work is based chiefly upon the following authorities: Agathias, Appian, Augustan History, J. B. Bury, Henry Fynes Clinton, George Kedrenos, Anna Komnene, Cassius Dio, Doukas (historian), Einhard, Eutropius (historian), George Finlay, Heinrich