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
Fall of the Western Roman Empire throughout and beyond the political collapse. The Fall of the Western Roman Empire was the process in which it failed to enforce its rule. The loss of centralized political control over the West, and the lessened power of the East, are universally agreed, but the theme of decline has been taken to cover a much wider time span than the hundred years from 376. For Cassius Dio, the accession of the emperor Commodus in 180 CE marked the descent "from a kingdom of gold to one of rust and iron"., while Gibbon also began his narrative of decline from rule