Edward Gibbon's six-volume History of the Decline and Fall of the Roman Empire (1776-88) is among the most magnificent and ambitious narratives in European literature. Its subject is the fate of one of the world's greatest civilizations over thirteen centuries - its rulers, wars and society, and the events that led to its disastrous collapse. Here, in volumes three and four, Gibbon vividly recounts the waves of barbarian invaders under commanders...