"Scarcely one third of the entire army escaped. Never, except in the battle of Cannae, had there been so destructive a slaughter recorded in our annals." Thus the Roman historian Ammianus Marcellinus recorded the battle of Adrianople, 9 August AD 378, which spelled the beginning of the end of the Roman Empire. Such a crushing Roman defeat by Gothic cavalry proved to the Empire, as well as to the Goths themselves, that the migratory barbarians were a force to be reckoned with. Valens, the Emperor of the East, was killed along with up to 40,000 Roman soldiers. Simon MacDowall tells the story of the misguided Roman plans to attack, the lack of adequate scouting that resulted in the surprise attack of Gothic cavalry, and puts forward the most recent theories as to the true location of the battlefield.