Winthrop Sargent was an author. He was the grandson of Winthrop Sargent. He wrote for the periodical press, especially on genealogical and historical subjects. His publications include History of an Expedition against Fort Duquesne in 1775, under Major-General Braddock, edited from Original Manuscripts, which was commended by George Grote, the historian, and was described by Washington Irving as "ably edited, with an admirable introductory memoir" (Philadelphia, 1855); The Loyalist Poetry of the Revolution (1857); The Journal of the General Meeting of the Cincinnati (1858); Loyal Verses of Joseph Stansbury and Dr. Jonathan Odell, with Introduction and Notes (Albany, 1860); Life and Career of Maj. John André (Boston, 1861); and Les États Confédérés et de l'esclavage (The Confederacy and Slavery; Paris, 1864). For many years he was engaged in preparing a catalogue raisonné of books relating to America, which he left unfinished.