Dame Emma Thompson threatened to quit this movie if the producers persisted in pushing actress Hayley Atwell to lose weight. Atwell said that Harvey Weinstein even insulted her over lunch by saying: "You look like a fat pig on-screen. Stop eating so much."
Castle Howard, which "played" Brideshead in this movie, was also used to represent the same location in Brideshead Revisited (1981).
David Yates was set to direct this movie, but had to step aside from the director's chair to direct Harry Potter and the Order of the Phoenix (2007) instead. While Yates was attached, Paul Bettany, Jennifer Connelly, and Jude Law were cast in the roles of Charles, Julia, and Sebastian, respectively. It was also announced that Chatsworth House in Derbyshire would be used as Brideshead.
Filmed in summer 2007, one of the rainiest summers on record in England. The crew suffered rainfall at nearly every location, with parts of Oxford and Yorkshire flooded. At one time cast and crew were stranded on their train. They even had to contend with rain while on-location in Venice.
For the Oxford scenes, real Oxford students were recruited to play their 1920s counterparts. For the scene where Charles and Sebastian first meet, real members of the exclusive Bullingdon Club can be seen behind him wearing their traditional blazers. A few of them can also be seen in the luncheon scene that takes place the next day.