Who is Alfred Stieglitz from On Photography and what is their importance?

Stieglitz (1864-1946) was an American photographer discussed at some length in chapter two of the text. Sontag asserts he was a "virtuos[o] of the noble image" (p. 6). Stieglitz worked to create photographs of items or persons he deemed significant in some way, and he was instrumental in making photography an acceptable art form. From 1903 to 1917 he published the serial Camera Week. He also displayed work in a famous New York gallery from 1905 to 1917. With Edward Steichen, Stieglitz created the Little Gallery of the Photo-Secession. Sontag asserts that Stieglitz's work was the most ambitiously Whitmanesque portrayal of photographs in American history.