The DAR Library was originally founded in 1896 with a collection of 126 books to be used by the genealogists who were verifying membership application for the DAR. Shortly after 1900, the library was opened to the public in rented space on F Street in Northwest Washington, DC.
In 1910, the DAR Library moved from F Street to the north gallery of Memorial Continental Hall with a collection that had grown to 5000 volumes.
By 1929, the collection had grown to 18,000 volumes and was moved from Memorial Continental Hall to the 2nd floor of the newly constructed Constitution Hall.
In 1949, the collection was moved back into Memorial Continental Hall in the space that had previously been the auditorium.
1966 saw the creation of the Seimes Microfilm Center (later re-designated as the Seimes Technology Center).
The early 2000s saw the advent of various digitization projects beginning with the online library catalog, the development of the Genealogical Research System (GRS), the digitization of the Genealogical Records Committee Reports (GRC) and the beginnings of the Patriot Records Project (PRP).