Tracing the path of the plague as it wrapped its deadly coils around Europe in the 14th century is easy. Simply follow the path of the traders. By 1346, rumors of a horrifying plague in the Orient were spreading over Europe, but they caused no alarm. The laws of infection were unknown. A plague in the Orient in 1346 was like a plague on Mars would be today. Too soon, the disease came across Asia. It raced through India, leaving behind cities of dead, then swept up into the Middle East. In the spring of 1347 it became a terrifying ritual of dehumanization in the massive cities of Constantinople and Cairo, where as many as 7000 people were buried in mass graves daily during the height of the plague (Ziegler, pg. 39).
Traditionally the story of the movement of the Black Death into Europe starts with a siege of the island-city of Caffa by a Tartar khan. Supposedly his forces became so depleted by the plague that he began to launch infected bodies over the walls of the city to counteract his losses. Although the residents of Caffa threw the bodies into the ocean as soon as they sailed over the walls, they still became infected and attempted to flee by boat. They sailed to Italy and thus set off a chain of events that would lead to the deaths of over 20 million people. This story is not very likely true, because of the etiology of the disease (in which it cannot be spread by dead bodies without extreme close contact in enclosed spaces) (Tuchman, pg. 92). Yet, as the Dictionary of the Middle Ages says, "...however accurate the particulars of the Caffa account, the story tells a great deal about the mechanism of the plague's spread. It moved overland until it reached the terminus of European sea travel. Once there, like an invading army it followed major routes of trade and communication, traveling across the open seas, up rivers, and along major highways..." (Volume II, pg. 258). In reality, the Black Death came through hundreds of tiny ports all along the Mediterranean. Here the new technologies of the age contributed to the massive effect of the disease: by this time, all of Christendom was connected by an elaborate series of trade routes and communication lines along which thousands of possibly infected traders traversed daily. Italy, the most urbanized, economically sophisticated country at the time, was the hardest hit because of its trade connections.
The Black Death Part 5: Italy