Sir William Henry St John Hope

Sir William Henry St John Hope (1854–1919) was an English antiquary.

Hope was a master at Rochester Grammar School in Kent, a post he continued to hold until his appointment in 1885 as Assistant Secretary of the Society of Antiquaries.

Hope was interested in archaeology and heraldry since boyhood, and his earliest works were on the subject of the monumental brasses of English churches. His major work was his Architectural History of Windsor Castle, began in 1893 with the approval of Queen Victoria, and completed twenty years later in 1913, an undertaking for which he was knighted. His other works include Stall-plates of Knights of the Garter, Heraldry for Craftsmen and Designers and A Grammar of English Heraldry.