The film accepts at face value the 1873 statement by Madison Hemings ( James Earl Jones ) that he and the other five children of Sally Hemings were all fathered by Thomas Jefferson. At the time this film was released this assertion was much more controversial than it became later. Three years after this film was released, extensive DNA testing on Sally Hemings's many descendants strongly confirmed that Jefferson was almost certainly the father of all six. (The tests were done in 1998-1999, and the results published in 2000.)
As of 2022, the Thomas Jefferson Foundation, which is in charge of Jefferson's historical estate in Monticello, accepts the findings (and includes extensive information about the Hemings family and Jefferson as a slave-owner on both the tour and their website), while the Thomas Jefferson Heritage Society (founded shortly after the DNA study) disputes the conclusions.
Gwyneth Paltrow's real life mother, Blythe Danner, played Martha Jefferson in 1776 (1972) the mother of her character. Nolte and Danner also played husband and wife in The Prince of Tides (1991).
Christopher Reeve was considered by director James Ivory to play Jefferson, but studio pushed for the more bankable Nick Nolte for the lead.
Sally Hemings' gown made from the patterned gray fabric selected by Thomas Jefferson and Mrs. Cosway is the same costume worn by Jessica Oyelowo (Sarah) in Sleepy Hollow (1999), and by Billie Piper (Fanny Price) during the play rehearsal scene in Mansfield Park (2007).