Alfred Stieglitz promoted Georgia O'Keeffe's art through his New York gallery known as 291.
The gallery was formally called the Little Galleries of the Photo-Secession, but it became widely known as “291” because of its address at 291 Fifth Avenue. Stieglitz opened it in 1905, and it became a key venue for photography and European and American modern art.
O'Keeffe's charcoal abstractions were shown there in 1916 after the photographer and gallerist Anita Pollitzer brought them to Stieglitz. The exhibition helped introduce O'Keeffe to New York's avant-garde art world.
Stieglitz later operated other galleries, including the Intimate Gallery and An American Place. Those names are related to his career, but 291 was the gallery associated with the earliest public promotion of O'Keeffe's work.