When Pope Leo rode out of Rome in 452 to meet Attila the Hun, he had no arms, no army, no bodyguards, no great retinue of ambassadors and advisers. Only a few churchmen and lesser officials of the enfeebled and fading Roman Empire accompanied him. Attila came to the encounter leading a large, well-armed, battle-hardened army of Huns on horseback. Having plundered northern Italy, they were on their way south with the apparent intention of sacking Rome. Leo had to convince Attila to spare the center of Western civilization. Here, in this essay by award-winning historian Charles L. Mee Jr. is the surprising story of that fateful encounter and its aftermath.