Anyone who has tried to construct the history of the population of a local area over decades or centuries will know the frustration and tedium of rendering population totals from different sources comparable. Reported populations often relate to slightly different geographical areas, and are defined in different ways (for example some include temporary visitors, others do not; some include members of the armed forces, others do not). Inconsistencies like these are common even in so ostensibly standard a series as successive decadal censuses.

In this volume, E. A. Wrigley has prepared a new set of population tables for the first six English censuses of 1801 through 1851. The output of the project consists of two sets of tables, in each of which the population of England in the six censuses is presented for a range of geographical areas built up as aggregations of the smallest useful units (parishes in southern and Midland England and townships in the northern counties). The first set, which Wrigley terms “A” for “Ancient,” uses the traditional hundreds and ancient counties. The second, “M” for “Modern,” set is based around the new administrative divisions (registration districts) and subdivisions (registration subdistricts) used in 1851 following the introduction of the civil registration of births, marriages, and deaths. In each case, the composition of the smallest units— the building blocks used in the census geography constructed for this volume—was standardized on the 1831 census.

Within each of the “A” and “M” sets, two groups of tables are presented. The first offers the original populations as published in the census volumes, corrected only for manifest inconsistencies or boundary changes. The second is the result of three other corrections. (1) Men who were in training with the militia (volunteer reserve forces who were particularly numerous during the Napoleonic Wars) were recorded separately in the censuses for each county and not included in any parish totals: they have been redistributed into their “home” localities. Their numbers were substantial in some counties (more than 1 in 20 of the male population in Hertfordshire and Cambridgeshire, for example). (2) Inflation factors to account for underenumartion of babies and young children have been applied. (3) A further correction was made for men recorded as being in the regular armed forces—as distinct from the militia, who were non-regular.

The book itself consists of three elements. The first is a series of five chapters describing the early English population censuses and the calculations Wrigley has carried out in order to produce the “A” and “M” tables. The second consists of the summary tables from both sets relating to hundreds in the “Ancient” series and registration districts in the “Modern” series. There were 664 hundreds in England in 1831 and 576 registration districts in 1851. The third element is a CD-ROM which includes the population totals from both sets for smaller geographical units (registration subdistricts in the “Modern” series, and parishes or townships in both series).

The first chapter in the textual part of the book describes the history of the early English censuses. Chapter 2 describes the process by which the first group of tables in each set was constructed, a process which consisted of the creation of a set of geographical units the boundaries of which do not vary over time, and the correction of errors and completion of missing data in the original tabulations. These errors and omissions are different from those discussed in Chapter 3, which relate to the allocation to their places of permanent residence of men who were serving in the armed forces or the militia, and the replacement of underenumerated infants and children.

In an earlier exercise, Wrigley has prepared new estimates of the populations of English counties between 1600 and 1800 (see Wrigley, “Rickman Revisited: The Population Growth Rates of English Counties in the Early Modern Period.” Economic History Review 62, no. 4 (2009): 711–35). In Chapter 4 of this book, he integrates his new estimates for the first half of the nineteenth century with these earlier estimates to produce a rich picture of the variation in regional population growth rates associated with industrialization. For the period 1760–1800 the estimates of the hundredal populations which he prepared with reference to Rickman's parish register abstracts can be linked to the new census estimates to produce a history and geography of population growth at the subcounty level spanning almost a century.

Chapter 5, written jointly with Max Satchell, describes the Geographical Information System which was constructed to produce areal data for the geographical units used in the population tables. This is based on R. J. P. Kain and R. R. Oliver's The Tithe Maps of England and Wales: A Cartographic Analysis and County-by-County Catalogue (Cambridge: Cambridge University Press, 1995) and the main task was to adjust Kain and Oliver's digitized maps to represent the new administrative units used in the 1851 census.

From one perspective, Wrigley's book is about the denominators (or exposed to risk) used in computing demographic rates and, as actuarial students will confirm, obtaining accurate and consistent denominators is a notoriously tedious exercise. Historical demographers have reason to be very grateful to Wrigley for carrying out the unglamorous, painstaking, at times unexciting, but fundamental research reported in this volume.

Population totals, however, are valuable in themselves. The evolution of the number of people living in a particular locality relates to many important questions about economic and social change. Wrigley's labors have provided for the first time a sound and consistent base on which to construct estimates of regional and local population trends in the country during the first half of the nineteenth century. The range of research topics which will profit from these new tables is wide, from explorations of the relationship between population change and changes in the economic structure to estimates of local migration flows using the demographic accounting equation. I expect that this book will therefore be a standard work of reference for many years to come.