- In December 2009, Diane ranked #88 on the Maxim Hot 100 List.
- Was a finalist in Elite’s 1992 Look Of The Year competition at age 15.
- Had to gain 15 lbs for Troy (2004) because director Wolfgang Petersen wanted her to appear rounder. She has since lost the weight.
- She has a younger brother, Stefan.
- Modeled under her birth name, Diane Heidkrüger, in the mid to late-1990s.
- Originally a ballet dancer, but quit dancing due to an injury at the age of 18.
- German citizen.
- Shares a birthday with philosopher Jacques Derrida, male model Travis Fimmel, and actors Brigitte Nielsen, Irène Jacob, Brian Austin Green and Scott Foley.
- Trained at the Cours Florent and won the Classe Libre award for best actor in her year.
- She is right-handed.
- People magazine included Diane in its annual “50 Most Beautiful People in the World” issue in 2004.
- Was listed as a potential nominee on the 2005 Razzie Award nominating ballot. She was suggested in the Worst Supporting Actress category for her performance in the film Troy (2004), however, she failed to receive a nomination.
- Is an active supporter of UNICEF.
- Learned Latin in school for eight years.
- She is fluent in English, French and German.
- Learned Russian for Les brigades du Tigre (2006).
- Lived three weeks in a mental hospital to shoot Frankie (2005). She is the only actress in that film, all patients are real.
- She always dubs herself in three languages.
- Member of the jury at the 58th Berlin Film Festival in 2008.
- Is very good friends with ex-husband Guillaume Canet.