This article explores how plague—as an idea—became an ahistorical independent agent of historical change. It focuses on the case of the Justinianic Plague (ca. 541–750 C.E.), the first major recorded plague pandemic in Mediterranean history, which has increasingly been used to explain significant demographic, political, social, economic, and cultural change during late antiquity (ca. 300–800 C.E.). We argue that the Justinianic Plague retains its great historiographic power—namely, its supposed destructive impact over two centuries—because it evokes a terrifying myth of what plague should do rather than because of conclusive evidence of what it did. We define this historiographic power as the plague concept. It includes three key features: extensive chronology (lasting for two centuries), mortality (catastrophic death toll), and geography (global). The plague concept is built on three interdisciplinary types of evidence (here termed truisms): rats, climate, and paleogenetics. Our article traces how scientists constructed the plague concept in the first half of the twentieth century, and how historians entered the discussion in the last third of that century. As historians engaged in Justinianic Plague research, they used the plague concept to frame their arguments without problematizing its presence or contesting features that scientists had constructed decades earlier.
Article published in The American Historical Review.