Sowerby served as a British counterintelligence agent in France during World War I and moved to the United States in 1923, eventually finding employment in the rare book department of the New York Public Library and with A. S. W. Rosenbach.
Sowerby Bridge | Sowerby | Millicent, South Australia | Millicent Fawcett | James Sowerby | Millicent Huxtable | Millicent Fenwick | Millicent | Leo Sowerby | Sowerby (UK Parliament constituency) | Millicent Shelton | Millicent Library | Millicent Leveson-Gower, Duchess of Sutherland | Millicent Armstrong | James De Carle Sowerby | Elizabeth Millicent Chilver |