Historiography of the fall of the Western Roman Empire Historiography of the fall of the Western Roman Empire The causes and mechanisms of the Fall of the Western Roman Empire are a historical theme that was introduced by historian Edward Gibbon in his 1776 book "The History of the Decline and Fall of the Roman Empire". He started an ongoing historiographical discussion about what caused the Fall of the Western Roman Empire, and the reduced power of the remaining Eastern Empire, in the 4th–5th centuries. Gibbon was not the first to speculate on why the Empire collapsed, but he was the first to give a well-researched and well-referenced account.
Fall of the Western Roman Empire of Commodus, after a number of introductory chapters. Arnold J. Toynbee and James Burke argue that the entire Imperial era was one of steady decay of institutions founded in republican times, while Theodor Mommsen excluded the imperial period from his Nobel Prize-winning "History of Rome" (1854–56). As one convenient marker for the end, 476 has been used since Gibbon, but other key dates for the fall of the Roman Empire in the West include the Crisis of the Third Century, the Crossing of the Rhine in 406 (or 405), the sack of Rome in 410, and the death of Julius