Ray Allen Billington (September 28, 1903 in Bay City, Michigan - March 7, 1981 in San Marino, California) was an American historian who researched the history of the American frontier and the American West, becoming one of the leading defenders of Frederick Jackson Turner's "Frontier Thesis" from the 1950s to the 1970s,[1][2] expanding the field of the history of the American West. He was a co-founder of the Western History Association in 1961.[3]