Further reading:

Thomas R. Morris, “Richard Henry Cardwell (1846-1931),” Dictionary of Virginia Biography (1998).

Research collections:

Library of Virginia (Personal Papers Collection)
Richmond, Va.
Frank G. Ruffin Scrapbooks and Papers, 1874-1892; 33 leaves and 8 p.
Includes a letter to Cardwell regarding remarks he made in a speech in the Virginia House of Delegates.

University of Virginia (Albert and Shirley Small Special Collections Library)
Charlottesville, Va.
Whittle Family Papers, 1753-1960; 650 items.
Cardwell is represented in the Supreme Court correspondence of Stafford Gordon Whittle, 1901-1919.