This work investigates the complex social and cultural evolution of ethnic relations between the English and the Normans following the Conquest of 1066. Hugh M. Thomas, a specialist in medieval history, utilizes a wide array of primary sources including chronicles, legal documents, and administrative records to trace the transition from overt hostility to eventual assimilation. The book argues that the formation of a unified English identity was a protracted process shaped by political necessity, intermarriage, and shifting power dynamics over the course of 150 years.

Historians and scholars frequently cite this text as a definitive examination of post-Conquest identity formation. Readers often note the academic density of the prose, which provides a rigorous and nuanced look at medieval social structures.