Gale / Gale Virtual Reference Library.
Available online. (W&L subscription)
Four-volume set (2009) contains nearly 500 entries on American writers which "analyze an author's work as a reflection of the heritage, traditions and experiences of the author's personal life and the beliefs, events, and lifestyles of the United States at the time."
Links will be maintained in several locations in the library Web site, including this subject listing.