This volume serves as a critical expansion of the American National Biography, addressing the need for updated and inclusive historical documentation of figures who shaped the United States. Edited by John A. Garraty and Mark C. Carnes, this supplement provides rigorous academic profiles that extend the original project's scope. It utilizes scholarly research and primary source bibliographies to maintain the high standards of the American Council of Learned Societies, ensuring that the historical record remains both comprehensive and current.

Experts and historians regard this supplement as a necessary addition for libraries and research institutions maintaining the full American National Biography set. Readers frequently note the academic density of the prose and the high level of detail provided in each biographical entry.