Fig. 1.

(Top Left) Part of a will proved in the PCC, dated 18 December 1644 (34). (Top Center) A parish register page from St Giles without Cripplegate, August 1665 (38). Image credit: Wellcome Collection, licensed under CC BY 4.0. (Top Right) One of the LBoM, for the week beginning 26 September 1665 (photo by Claire Lees, taken in the Guildhall Library, City of London). (Bottom) Mortality in London, United Kingdom, 1340 to 1380 and 1540 to 1680, aggregated 4-weekly, plotted on a log scale. The three distinct sources of data (SI Appendix, Table S2) are last wills and testaments of Londoners whose wills were probated in the Court of Husting (14th century) or the PCC (16th to 17th centuries), weekly aggregations of burials listed in extant parish registers (29), and weekly plague deaths listed in the LBoM (27). Major plague years are highlighted in yellow. Aside from these and various minor plague years, there are notably unusual patterns during an epidemic of sweating sickness in 1551 (ref. 29, p. 70), the influenza epidemic of 1557 to 1559 (ref. 29, p. 70) (which coincided with the end of the reign of Bloody Mary I and the ascension of Elizabeth I in 1558 [indicated by a crown icon]), and the absence of a monarch during the Interregnum from 30 January 1649 to 29 May 1660.