Which photographer founded the 291 gallery and promoted Georgia O'Keeffe's early work?

Alfred Stieglitz founded and operated the 291 gallery, where he promoted Georgia O'Keeffe's early work.

Stieglitz was an American photographer, publisher, and leading advocate of modern art. His gallery at 291 Fifth Avenue in New York operated from 1908 to 1917 and became known for presenting European avant-garde art alongside work by American artists. He exhibited O'Keeffe's drawings there beginning in 1916.

Their professional relationship developed into a personal one. O'Keeffe and Stieglitz married in 1924, although O'Keeffe's artistic identity remained independent. Stieglitz photographed her extensively and organized exhibitions of her paintings and drawings.

Stieglitz is sometimes confused with Edward Steichen, another important photographer associated with early twentieth-century exhibitions, or with Paul Strand, whose photography he also supported. The 291 connection specifically points to Stieglitz and the gallery's address, not to a museum or art school.