George Biddle studied at the Academie Julian in Paris, 1911/12, and the Pennsylvania Academy of Fine Arts, Philadelphia, 1912/14. During these years he met Mary Cassatt and studied painting in Giverny, France, with Frederick Frieseke. On a later trip he met Jules Pascin. In the 1920s Biddle set up a studio in Greenwich Village, New York City. Artist friends from the 1920s include Arthur B. Davies, Charles Demuth, Adolf Dehn, Yasuo Kuniyoshi, and Diego Rivera with whom Biddle travelled to Mexico in 1928.
Biddle first made prints in 1914 when he studied in Munich with a Professor Heinemann. Back in this country in the 1920s and 30s he worked with master printers George C. Miller in New York and Lawrence Barrett in Colorado Springs, and soon developed distinct lithographic techniques.
During the Great Depression of the 1930s, it was George Biddle who suggested to his old Groton School friend, President Franklin D. Roosevelt, that artists have a part in the New Deal, resulting in the Federal Art Project. Biddle was a founding member of the Contemporary Print Group, 1933, and an active participant in the first American Artists Congress, 1936. He was chairman of the US War Artists Committee, 1943, served as an artist/observer of the Nuremberg war trails, 1947, and was on the federal Fine Arts Commission, 1950. Biddle made murals for the Chicago World's Fair, 1933, the Department of Justice, Washington, DC, 1936, the Biblioteca Nacional, Rio de Janeiro, Brazil, 1942, and the Supreme Court building, Mexico City, Mexico, 1945.
Biddle's teaching career began at the Colorado Springs Fine Arts Center, Colorado, 1937; New York artist friends Adolf Dehn and Yasuo Kuniyoshi were there as well. Biddle also taught at the Otis Art Institute, Pacific Palisades, California, 1941, and in Saugatuck, Michigan, 1947. He was artist-in-residence at the American Academy, Rome, 1951/52. Also in the 1950s he made several trips to Haiti, and travelled to Japan, Southeast Asia, and India.