Which photographer founded the gallery 291 associated with Georgia O'Keeffe?

Alfred Stieglitz founded the gallery known as 291, which became closely associated with Georgia O'Keeffe. The gallery operated at 291 Fifth Avenue in New York and was originally called the Little Galleries of the Photo-Secession.

Stieglitz first encountered O'Keeffe's charcoal abstractions through drawings sent to him by artist and teacher Anita Pollitzer. He exhibited some of those works in 1916 at his gallery without O'Keeffe's initial permission, beginning a professional relationship that changed both their lives.

Stieglitz was an important photographer, publisher, and promoter of modern art in the United States. He and O'Keeffe married in 1924. The gallery's address supplied its famous name, so 291 refers to a location rather than a separate artistic movement or a painting title. Stieglitz closed the gallery in 1917, but his influence on O'Keeffe's early career continued.