Alfred Stieglitz (1864–1946) was a celebrated photographer and a leading champion of modern painting in America. In 1905 he established the Little Galleries of the Photo-Secession, known as "291" for its address on Fifth Avenue. The gallery promoted paintings and photographs that reflected Stieglitz's belief that true innovation derived from expressive, formal experimentation. Dove had his initial solo exhibition at 291 in 1912, and O'Keeffe exhibited her drawings and watercolors there in 1916 and 1917. Stieglitz's admiration for O'Keeffe and her work was immediate, and he effused to Dove that "O'Keeffe is truly magnificent . . . she a purer form of myself." Stieglitz and O'Keeffe married in 1924.