THE BLACK DEATH, the first outbreak of medieval plague that swept through Eurasia and Northern Africa in the mid-fourteenth century, was one of the most devastating epidemics in human history. The epidemic killed tens of millions of people in Europe alone within a very short period of time (Benedictow 2004; Cohn 2002; Dols 1977; Wood, Ferrell, and DeWitte-Avina 2003). This disease initiated or enhanced social, demographic, and economic changes throughout Western Eurasia and Northern Africa (see, for example, essays by Borsch 2014, Carmichael 2014, Colet et al. 2014, and Green 2014—all in this issue), and thus has attracted the interest of a variety of researchers for decades. In addition to its importance in shaping events hundreds of years ago, the Black Death continues to be of interest today, in part because the epidemic was caused by the same pathogen that causes modern plague, the bacterium Yersinia pestis. Given molecular evidence that the Plague of Justinian (c. sixth to eighth centuries CE) was also caused by Y. pestis (Harbeck et al. 2013; Wagner et al. 2014; Wiechmann and Grupe 2005), the Black Death was a terrible manifestation of a disease that has affected humans for nearly fifteen hundred years. The continued existence and threat of plague means that it is crucial to understand the extent of the geographic and temporal variation of the disease so that we might best be prepared for its effects on our species in the future.

This paper focuses on the reconstruction of medieval Black Death mortality patterns, particularly those patterns that have been estimated using the skeletal remains of victims of the epidemic in the mid-fourteenth century. Such research is essential for several reasons. Though it is now clear from molecular evidence, particularly the results of recent whole genome sequencing studies, that the Black Death was caused by Y. pestis (Bos et al. 2011; Drancourt and Raoult 2002; Haensch et al. 2010; Raoult et al. 2000; Schuenemann et al. 2011), this is a relatively recent discovery. The most convincing and least controversial molecular studies, which have yielded sequences specific to Y. pestis and used samples clearly dated to the fourteenth-century epidemic (rather than merely suspected victims or victims of more recent historic epidemics), have all been published since 2009 (Bos et al. 2011; Haensch et al. 2010; Schuenemann et al. 2011).