How does Wall Street (photograph) elucidate its Background?
In 1907, as a young teen, the artist, Paul Strand, enrolled in New York's Ethical Culture Fieldston School.  There, Strand was under the tutelage of documentary photographer Lewis Hine.  Hine introduced Strand to the modernist photographer Alfred Stieglitz.  Stieglitz was heavily influential in the art world at the time, pushing for photography to be considered an art form and opening his own gallery, the 291 Gallery, with another influential photographer Edward Steichen, to promote modernist art.  Stieglitz's colleagues were striving to receive acceptance for photography as a form of art.  Stieglitz would become a mentor and artistic comrade of Strand, with both influencing each other for the rest of their careers.
With Stieglitz's influence, Strand explored the pictorialist style, creating works with soft focus, and posed scenes.  Photographs aimed to look like paintings.  Around 1915, Strand and Stieglitz sought to change their aesthetics and made the march toward straight photography.  Stieglitz pushed Strand to involve real-life subjects and less manual manipulation of the print and utilized the style that was innate to the methods and materials of photography.  Strand interpreted this request from Stieglitz and created this new style that incorporated high contrasts, clean lines, and emphasis on shape.  These elements come from how Strand captured the real life and movements of subjects, not how he posed or manipulated them.
Lewis Hine the 291 Gallery Ethical Culture Fieldston School Edward Steichen 291 Gallery Alfred Stieglitz Paul Strand straight photography