Nancy Nichols Barker (December 26, 1925 – March 30, 1994) was an American historian, editor, and professor at the University of Texas at Austin.
Barker was the author of several books, including The Empress Eugenie and the Foreign Policy of the Second Empire (1967), The French Experience in Mexico, 1821-1861: A History of Constant Misunderstanding (1979), and Phillippe, Duke of Orleans (1640-1701): Brother to the Sun King (1989).
With Marvin L. Brown Jr., Barker edited Diplomacy in an Age of Nationalism: Essays in Honor of Lynn Marshall Case (1971).
Her work as the translator and editor of The French Legation in Texas won her the Gilbert Chinard Prize, the Summerfield G. Roberts Award, and the Award of Merit from the American Association for State and Local History.
She also won the American Historical Society's Leo Gershoy Award in 1989 for Brother to the Sun King.