In 1338, among a scattering of obscure villages just to the west of Lake Issyk-Kul, Kyrgyzstan, people began dropping dead in droves. Among the many headstones found in the cemeteries of Kara-Djigach and Burana, one can read epitaphs such as “This is the grave of Kutluk. He died of the plague with his wife.” Recently, ancient DNA exhumed from these sites has confirmed the presence of the plague bacterium Yersinia pestis, cause of the condition that became known as the Black Death. The strain detected in those remote graveyards of Central Asia has been identified as the most recent common ancestor of the plague that went on to kill as much as 60% of the Eurasian population in the great pandemic of the 14th-century.