Robert Ridgway was an American ornithologist specializing in systematics. He was appointed in 1880 by Spencer Fullerton Baird, secretary of the Smithsonian Institution, to be the first full-time curator of birds at the United States National Museum, a title he held until his death. In 1883, he helped found the American Ornithologists' Union, where he served as officer and journal editor. Ridgway was an outstanding descriptive taxonomist, capping his life work with The Birds of North and Middle America (eight volumes, 1901–1919).

In his lifetime, he was unmatched in the number of North American bird species that he described for science. As technical illustrator, Ridgway used his own paintings and outline drawings to complement his writing. He also published two books that systematized color names for describing birds, A Nomenclature of Colors for Naturalists (1886) and Color Standards and Color Nomenclature (1912). Ornithologists all over the world continue to cite Ridgway's color studies and books.