Passage: The Dark Knight was nominated for eight Academy Awards for the 81st Ceremony, breaking the previous record of seven held by Dick Tracy for the most nominations received by a film based on a comic book, comic strip, or graphic novel. The Dark Knight won two awards: Best Supporting Actor for Heath Ledger and Best Sound Editing. It was additionally nominated for six others, these being Best Art Direction, Best Cinematography, Best Sound Mixing, Best Visual Effects, Best Makeup, and Best Film Editing. Heath Ledger was the first posthumous winner of the Best Supporting Actor award, and only the second posthumous acting winner ever (Peter Finch posthumously won the Best Actor award for his performance in the 1976 film Network). In addition, Ledger's win marked the first win in any of the major Oscar categories (producing, directing, acting, or writing) for a superhero-based film. Notably, Richard King's win in the Sound Editing category blocked a complete awards sweep of the evening by the eventual Best Picture winner, Slumdog Millionaire. Although it did not receive a Best Picture nomination, the show's opening song paid homage to The Dark Knight along with the five Best Picture nominees, including host Hugh Jackman riding on a mockup of the Batpod made out of garbage. In spite of the film's critical success, the film was noticeably absent from the Best Picture nominee list, prompting controversy and led many to criticize the Academy Awards for "snubbing" the film. There was speculation that the Academy of Motion Picture Arts and Sciences later changed their number of Best Picture nominees to ten, instead of the traditional five, because of the film's omission. In a question-and-answer session that followed the announcement, the Academy's then president Sidney Ganis said; "I would not be telling you the truth if I said the words Dark Knight did not come up."A British-American production, the film was nominated for the 2009 Goya Award for Best European Film. It had a nomination in Japan for the 2009 Seiun Awards...

Question: who was Heath Ledger?
the first posthumous winner of the Best Supporting Actor award