This work investigates how the rapid urbanization of Europe between 1830 and 1930 fundamentally altered the practice, influence, and social role of organized religion. Hugh McLeod, a prominent historian of modern religion, utilizes a comparative framework to analyze the decline of traditional church attendance and the emergence of new secular and religious identities in major metropolitan centers. By examining the intersection of industrialization, class structure, and ecclesiastical policy, the author argues that the city acted as a primary catalyst for the secularization of European society.

Historians and sociologists frequently cite this text as a foundational study for understanding the relationship between urban development and religious decline in the nineteenth and twentieth centuries. Experts highlight the author's meticulous use of comparative data to illustrate the diverse ways different European cultures navigated the challenges of modernity.