<Tr> <Th> Known for </Th> <Td> Photography </Td> </Tr> <Tr> <Th> Spouse (s) </Th> <Td> Georgia O'Keeffe (m . 1924; his death 1946) </Td> </Tr> <P> Alfred Stieglitz (January 1, 1864--July 13, 1946) was an American photographer and modern art promoter who was instrumental over his fifty - year career in making photography an accepted art form . In addition to his photography, Stieglitz was known for the New York art galleries that he ran in the early part of the 20th century, where he introduced many avant - garde European artists to the U.S. He was married to painter Georgia O'Keeffe . </P> <P> Stieglitz was born in Hoboken, New Jersey, the first son of German - Jewish immigrants Edward Stieglitz (1833--1909) and Hedwig Ann Werner (1845--1922). His father was a lieutenant in the Union Army . He had five siblings, Flora (1865--1890), twins Julius (1867--1937) and Leopold (1867--1956), Agnes (1869--1952) and Selma (1871--1957). Alfred Stieglitz, seeing the close relationship of the twins, wished he had a soul mate of his own during his childhood . </P>

Who was the photographer that was the leader and catalyst for photography as an art form