The Black Death: A Pandemic Follows the Trade Routes

The Black Death of the 1340s shows the dark side of connection. Caused by the bacterium Yersinia pestis, plague spread along caravan routes and shipping lanes from Central Asia to the Black Sea, the Middle East, North Africa and Europe. Ancient DNA research published in 2022 traced an early outbreak to the region near Lake Issyk-Kul in modern Kyrgyzstan around 1338–1339.

Genoese ships carried the disease from Caffa on the Black Sea to Messina in Sicily in 1347, and within a few years it had killed perhaps a third to a half of Europe's population, with heavy losses in Cairo and other cities too. The consequences were profound: labour shortages raised wages in parts of Europe, some communities blamed outsiders, and Jewish communities suffered terrible persecution. Cities developed new public-health tools, including quarantine, which became a lasting response to disease in a connected world.