Born to Charles H. Aitken and Katherine A. Higgens[1] in San Francisco, California, Aitken studied there at the Mark Hopkins Institute of Art [also called the California School of Design – now the San Francisco Art Institute] with Douglas Tilden. From 1901 until 1904 he was an instructor at the Institute.
During this period, Aitken in 1900 designed San Francisco's original municipal flag; the design was in use from 1900 until sometime in the early 1920s.[2]
In 1903, he sculpted the Victory figure for the top of the Dewey Monument, which still stands in San Francisco's Union Square.
Aitken also enjoyed success as a designer of coins and medals. He sculpted the $50 gold commemorative (round and octagonal) for the Panama-Pacific Exposition of 1915, as well as the official medal of the event. He also created the Missouri Centennial half dollar of 1921, following it a decade and a half later with the California Pacific International Exposition half dollar of 1935–1936. In the medallic arena, Aitken sculpted the American Numismatic Society's 1921 medal commemorating Marshal Foch's visit to the United States; the 15th issue of the Society of MedalistsOmnia Vincit Amor, 1937; the Medal of the National Academy of Design; and the Medal of the National Sculpture Society.
Goode, James M. The Outdoor Sculpture of Washington, D.C., Smithsonian Institution Press, Washington, D.C., 1974
Gurney, George, Sculpture and the Federal Triangle, Smithsonian Institution Press, Washington D.C., 1985
Hunter, Marie Nau, Missouri and Mississippi: Robert Ingersoll Aitken's Sculpture in Jefferson City, Missouri, Master's Thesis, University of Missouri-Columbia, 1996
Opitz, Glenn B, Editor, Mantle Fielding’s Dictionary of American Painters, Sculptors & Engravers, Apollo Book, Poughkeepsie, NY, 1986