During the Great Depression, Franklin Roosevelt established the Farm Security Administration (FSA) under Rexford Tugwell, a member of the President's so-called brain trust. The goal of the FSA was to assist agriculture in recovery from drought and economic collapse.
In addition, the FSA appointed Roy Stryker (far right in picture) to head a FSA historical section which would document recovery and the effects of the depression on American citizens. This effort included a massive effort to photograph everything about the US during this time. He hired some of the best photographers in America to take pictures and send them back to Washington for cataloging. Over the course of the decade, the photographic collection of the FSA became a treasure trove of Americana. Eventually, the collection was housed in the Library of Congress. Watch the instructional video on Roy Stryker and the FSA.
When war was declared, the FSA was merged into the Office of War information. Most of the original FSA photographers dispersed into commercial photography like Look and Life magazines. The OWI hired Gordon Parks, Esther Bubley, and Marion Post Wolcott to photograph the homeland at war.