Georgia O'Keeffe's charcoal abstractions were first exhibited at Alfred Stieglitz's New York gallery, 291, in 1916. The gallery took its name from its address at 291 Fifth Avenue and became an important venue for modern European and American art.
O'Keeffe's friend Anita Pollitzer showed some of the drawings to Stieglitz without O'Keeffe's prior approval. Stieglitz recognized their importance and displayed them at 291. The exhibition brought O'Keeffe to the attention of influential members of New York's modernist art circle.
The event mattered because the drawings were abstract rather than conventional landscapes or portraits. Their flowing lines and restricted tones established themes that O'Keeffe would continue exploring in paintings, although she later worked in many different styles and media.
The gallery closed in 1917, but Stieglitz continued to promote O'Keeffe through later galleries, including the Intimate Gallery and An American Place. “291” is therefore a gallery name, not an exhibition title or a painting number.