Compiled in 1931 by University of Washington librarian Charles W. Smith and published under the auspices of the Pacific Northwest Library Association, A Union List of Manuscripts in Libraries of the Pacific Northwest serves as a foundational archival inventory designed to formalize and professionalize regional historical research. Building on his earlier bibliographies of published works, Smith meticulously aggregated and mapped the locations of unpublished primary sources—such as pioneer diaries, missionary letters, fur trade ledgers, and territorial government correspondence—scattered across various regional institutions. The catalog effectively centralized the disparate, raw textual artifacts of early Anglo-American settlement, transforming them into a cohesive, searchable database for academic historians.

A keen insight drawn from the work is how the bureaucratic cataloging of unpublished archival material functioned as a profound mechanism of epistemological enclosure; by strictly defining authentic historical "manuscripts" as the written, paper artifacts generated exclusively by white settlers, bureaucrats, and missionaries, Smith’s inventory institutionalized the absolute supremacy of the colonial written word. This seemingly neutral archival project structurally barred Indigenous oral histories, material records, and active cultural memory from the realm of legitimate, academically recognized "primary sources." Consequently, it guaranteed that the definitive history of the Pacific Northwest would be researched, written, and validated almost entirely through the literal handwriting of the very people who engineered its colonization.