Nancy Nichols Barker (1925–1994) was a prominent American historian and professor who specialized in 19th-century French history and diplomatic relations. She spent the majority of her academic career at the University of Texas at Austin, where she eventually became Professor Emeritus.
Barker's scholarship is noted for its focus on French influence in North America and Mexico, as well as European dynastic history. One of her most significant contributions to the field of Texas history was her work on The French Legation in Texas (published in two volumes between 1971 and 1973), which she translated and edited. This work provided a detailed account of diplomatic relations between the Republic of Texas and France during the mid-19th century.
In 1979, she published The French Experience in Mexico, 1821–1861: A History of Misunderstanding, which examined the complex economic and political factors leading up to the French intervention in Mexico. Her later research shifted toward French domestic royalty, resulting in the publication of Brother to the Sun King: Philippe, Duke of Orleans (1989), a definitive biography of Louis XIV's brother.
Throughout her career, Barker received numerous accolades for her research. She was a two-time recipient of the Gilbert Chinard Prize, awarded by the Society for French Historical Studies and the Institut Français d'Amérique, and was elected a Fellow of the Royal Historical Society. Her work is frequently cited for its rigorous archival research and its objective analysis of international diplomacy.