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Combining History and Historical Demography to Understand a Nineteenth Century City

Most major North American cities have their origins in the nineteenth century, combining internal migration with immigration from abroad to provide the labor force for a growing urban economy. Migrations seem always to create strong fault lines based on ethnicity, and a central theme in social research has been to understand how new groups are incorporated (or how they fail to incorporate) into mainstream life. Montreal provides a unique case because here the largest ethnic group was French, though the commercial elite were English, and a significant share of working class people were immigrants from Ireland. Language potentially linked the Irish with the English, but religion distinguished the British Protestants from Irish and French Catholics. This specific configuration sets the scene for Sherry Olson and Patricia Thornton’s (2011) study of the demographic history of Montreal from 1842 (population 35,000) to 1901 (population 325,000). The authors in this study bring together the results, some already published elsewhere, of a monumental project that was over two decades in the making. A common method for historians is the biography, where general trends of continuity and change in a society are made visible by following the life course of a single person. Olson and Thornton draw a much larger sample of lives to follow, which they calculate included about 0.5% of the city population at any given time, including as many as four generations in a single family, and representing the three main ethnic communities. Increasingly, the sources used by genealogists and historians, once requiring intensive effort to marshal the details of even a single family or neighborhood over time, are be-