The Black Death

In the Chüy Valley, near Lake Issyk-Kul in what is now Kyrgyzstan, a number of tombstones dated 1338 and 1339 say that the person buried there died of "pestilence." In 2022 scientists found DNA of the plague bacterium, Yersinia pestis, in the dead there. They argue that this strain was the ancestor of the plague that later swept west, and that the Black Death arose in central Eurasia.

Scholars date the Black Death from 1346 to 1353, or from 1347 to 1352. It is usually traced to outbreaks around the Black Sea in 1346. Ships brought it to Sicily in October 1347. From there it spread through Italy, to the ports of France and Spain, and over the Alps. It began a "second plague pandemic" of outbreaks lasting nearly 500 years.

The toll is still argued. Nineteenth-century historians put it at a quarter of Europe's people or more. Many later studies, built on records from well-documented places, put it at about half, some 50 million people. Some estimates reach 60 percent for western Eurasia; others think the toll was lower. A 2022 study of ancient pollen from 261 sites tested these claims. In parts of Scandinavia, France, western Germany, Greece, and central Italy, farming declined sharply. In parts of central and eastern Europe, and in Ireland and Iberia, it went on and even grew. Death rates, the authors conclude, varied far more than historians had thought. The historian Daniel Curtis argued that less grain pollen shows fewer people but not necessarily plague deaths, and the authors replied.

Many library texts date from 1348 or soon after; their figures are estimates. The Plague Comes to Messina and Catania blames Genoese galleys for bringing the disease to Sicily. The Pestilence Comes to Florence, 1348, by Boccaccio, and After the Mortality: Florence, 1348, by Matteo Villani, describe Florence; I Buried My Five Children with My Own Hands records one man's losses in Siena. The Great Mortality in Paris, 1348–1349 reports the charge that Jews poisoned the wells and the massacres that followed. The Plague in the Bishop of Rochester's Household shows an English diocese with empty posts. The Plague Goes Town by Town, Muslims, Jews, and Christians Pray Together, and As If the Whole World Had Changed show Aleppo, Damascus, and North Africa. No writer of the time knew the cause; they spoke of God's anger, corrupted air, and contagion.