Industrialist, philanthropist, Andrew Carnegie financed the construction of over 2,400 libraries worldwide. In San Francisco, his offer of $750,000 for a central library and several branches was shelved for twelve years due to bitter class politics. Ex-mayor James D. Phelan drew a sharp rebuke and a rare admonition from Carnegie himself when he tried to take the money allotted to branches for his pet main library, which, said Carnegie, "will be entered only by the well-to-do who have books of their own."

The nomination of the seven San Francisco Carnegie branch libraries as local landmarks highlights their significance not only for their architectural excellence and national and state historical associations, but also for their specific connections with the cultural, political and social history of San Francisco.