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
Decline of the Byzantine Empire Decline of the Byzantine Empire The Byzantine Empire (the Eastern Roman Empire during the medieval period, after the fall of the Western Roman Empire) following the Sack of Constantinople (1204) slowly collapsed by Ottoman expansion. After crisis of the Gothic Wars it managed to re-establish itself in a golden age under the Justinian dynasty in the 6th century, and during the Early Middle Ages it continued to flourish even after the Muslim conquest of the Levant and the constant threat of Arab invasion. But in the High Middle Ages, under pressure from the Seljuk Empire, it suffered serious setbacks and