Historiography of the fall of the Western Roman Empire Roman civilisation which under-girded the Empire. According to this school, drawing its basic premise from the Pirenne thesis, the Roman world underwent a gradual (though often violent) series of transformations, morphing into the medieval world. The historians belonging to this school often prefer to speak of Late Antiquity instead of the Fall of the Roman Empire. In "The History of the Decline and Fall of the Roman Empire" (1776–88), Edward Gibbon famously placed the blame on a loss of civic virtue among the Roman citizens. They gradually entrusted the role of defending the Empire to barbarian mercenaries who eventually turned
Historiography of the fall of the Western Roman Empire catastrophic: Peter Heather, in his "The Fall of the Roman Empire" (2005), maintains the Roman imperial system with its sometimes violent imperial transitions and problematic communications notwithstanding, was in fairly good shape during the first, second, and part of the 3rd centuries AD. According to Heather, the first real indication of trouble was the emergence in Iran of the Sassanid Persian empire (226–651). As reviewed by one writer on Heather's writing, Heather goes on to state—in the tradition of Gibbon and Bury—that it took the Roman Empire about half a century to cope with the Sassanid threat, which it did