Georgia O'Keeffe lived and worked in Manhattan from 1918.
O'Keeffe moved to New York City in 1918 at Alfred Stieglitz's invitation. She lived in Manhattan, where she became immersed in the city's galleries, artists, and rapidly changing modern environment. The urban setting also inspired paintings of skyscrapers, including views of New York buildings from high windows.
Her New York period helped establish her reputation as an important American modernist. Although her work is often associated mainly with flowers and New Mexico, the city was a major subject during the 1920s and 1930s.
O'Keeffe later divided her time between New York and New Mexico. She moved permanently to New Mexico after Stieglitz's death in 1946, but the city remained an important part of her career history. Manhattan is the specific borough, rather than a general answer such as “New York.”