Just two movies about the Marquis?

There's a 1969 film De Sade, written by Richard Matheson that's more historically accurate. It stars Keir Dullea as Sade and John Houston as his uncle, Abbe de Sade. It's a much maligned film, and a bit abstract/avant garde at times, but I enjoy it far more than Quills. I think Dullea was miscast, but Houston and Lilli Palmer, as his mother-in-law, were great. The movie includes Sade's attraction to his sister-in-law, Anne, and his mother-in-law buying off Rose Keller (fact). There are some things that are based in truth, but given the dramatic license treatment. It helps if you've read a biography or two to understand some of what's going on. Example:

Sade loved the theatre and had one at his home, La Coste. The film shows the theatre, run-down and abandoned, and Sade meeting his uncle there. He "witnesses" an event from his past, his parents and future in-laws finalizing his marriage contract, played out on stage like a farce. The movie is non-linear and the theatre is a recurring theme. It's kind of trippy at times, but it's not as bad as people make it out to be. I thought it was a unique approach to telling part of Sade's story.

There's also a film of the RSC's 1967 production of the Marat/Sade with the great Patrick Magee as the Marquis, though it's probably rather hard to find: http://www.imdb.com/title/tt0060668/.

The full title of the play is "The Persecution and Assassination of Jean-Paul Marat as Performed by the Inmates of the Asylum at Charenton Under the Direction of the Marquis de Sade", by Peter Weiss.

If you liked this film, you'd love Salò. ;)

Tobe Hooper's Night Terrors features Sade in a sort of sub-plot (via flashbacks), played by Robert "Freddy Krueger" Englund. He also plays Sade's modern day descendant. It's basically a horror flick, but it has good moments. People hate this movie, and it is a mess, but it makes a lot more sense if you've read Philosophy in the Bedroom; part of the plot is drawn from the book and the character names of Eugenie and Chevalier come from the story as well. The script, without the slasher movie angle, is good, the movie could have been so much better as an erotic thriller. They even worked in Sade's keratitis/corneal opacity (although how he develops it in the movie is pure fiction).

One thing I like is that, unlike Quills, the movie uses passages from Philosophy as dialogue. The more Sade you've read, the more you'll recognize, even if it's a passing reference, like the Sodality of the Friends of Crime from Juliette, Dialogue Between a Priest and a Dying Man and a nod to the character of Rodin, from Justine.