This paper honours Michael Hicks's contribution to the understanding of the medieval English inquisitions post mortem (IPMs), both through his studies of aristocratic families and as director of Mapping the Medieval Countryside. This AHRC-funded research project created an online digital edition of the calendared IPMs from 1236 to 1447 and 1485 to 1509. It marked the culmination of almost two decades of recent work on the IPMs which had been initiated by the new series of calendars, for the years 1422–47, under the general editorship of Christine Carpenter. Professor Carpenter's project brought to light a great deal of new information about the production, use and value of the documents, much of which was summarised in her ‘General Introduction’ to the new series, and elaborated in more detail in the Companion volume edited by Professor Hicks. Still more has been uncovered during those stages of Mapping the Medieval Countryside which collected supplementary information on jurors, writs and other items for the online edition of CIPM, xviii–xxi (covering 1399–1422). The present paper explores discoveries which shed new light on the exchequer files of inquisitions post mortem.

The exchequer IPMs are widely used by historians: as is well known, they are sometimes more legible than the main chancery series of IPMs and can be used to supply gaps where the latter are damaged or missing. They also contain some inquisitions not found in the chancery series, notably those taken by the escheator by virtue of his office (ex officio or virtute officii), without the warrant of a writ. But the archival history of the documents – their origin, purpose and later use – is not well understood, with published sources offering brief accounts that are variously contradictory, confusing and mistaken. 3 Fuller understanding of that history has significant implications for our understanding of exchequer procedure and of the IPMs themselves.

It is at times a complicated story, due both to the original nature of the records and to their later history, and an initial summary will clarify what follows. Escheators’ records were radically reorganised by the Public Record Office in the early twentieth century in ways that have made it difficult to understand the original nature of the archive.