The presence of the Black Death traumatized Europeans on a scale greater than any previous calamity. "The mental shock sustained by all nations during the prevalence of the Black Plague is without parallel and beyond description," writes nineteenth-century German medical historian J. F. Hecker. Some modern historians believe that not until World War I (1914-1917) did Europeans again experience shock and trauma comparable in magnitude to what the Black Death inflicted on humanity.

Stunned Europeans also saw their society come to a standstill. Terrorized men and women ignored their daily duties and thought only of survival. Trade dropped off everywhere. Cathedral construction and other building projects slammed to a halt. Taxes and debts were not paid. Merchants and artisans closed their shops. Serfs abandoned their flocks and fields. Physicians, priests, law enforcement officers, and many other government officials fled Europe 's population centers and...