Plague and the Mongol conquest of Baghdad (1258)? A reevaluation of the sources

This paper reexamines the sources used by N. Fancy and M.H. Green in "Plague and the Fall of Baghdad (1258)" (Medical History, 65/2 (2021), 157-177). Fancy and Green argued that the Arabic and Persian descriptions of the Mongol sieges in Iran and Iraq, and in particular, in the conquest of Baghdad in 1258, indicate that the besieged fortresses and cities were struck by Plague after the Mongol sieges were lifted. This, they suggested, is part of a recurrent pattern of the outbreak of Plague transmitted by the Mongol expansion across Eurasia. Fancy and Green concluded that the primary sources substantiate the theory driven by recent paleogenetic studies indicating that the Mongol conquests of the thirteenth century set the stage for the massive pandemic of the mid-fourteenth century. The link between the Plague outbreak and the Mongol siege of Baghdad relies on three near-contemporaneous historical accounts. However, our re-examination of the sources shows that the main text (in Persian) has been significantly misunderstood, and that the two other texts (in Syriac and Arabic) have been mis-contextualized, and thus not understood properly. They do not support the authors' claim regarding Plague epidemic in Baghdad in 1258, nor do other contemporary and later Arabic texts from Syria and Egypt adduced by them, which we re-examine in detail here. We conclude that there is no evidence for the appearance of Plague during or immediately after the Mongol conquests in the Middle East, certainly not for its transmission by the Mongols.