Backstories are given in a deleted scene. Charles, Matthew and Fiona were at university together, and Gareth was a lecturer. Scarlett was found under Charles' kitchen table after a party and has lived there ever since.
Marisa Tomei turned down the role of Carrie, explaining "My grandfather was sick at the time, and I didn't want to leave (New York). I'm sure it would have been fine with him, but I felt like I didn't want to go anywhere." In a 2007 interview, Tomei also said that she will "always regret" turning it down.
Jeanne Tripplehorn was originally cast in the role of Carrie. However, the sudden death of her mother shortly before shooting was due to begin led her to leave the production and Andie MacDowell was cast instead.
When star Hugh Grant (and then partner Elizabeth Hurley) showed up at the London premiere of this movie, Hurley's seductive Gianni Versace outfit drew most of the media attention away from Grant, much to his obvious chagrin.
The trivia item below may give away important plot points.
Subsequently in Love Actually (2003), also written by Richard Curtis, the song Love Is All Around is again featured quite predominately in the plot with Billie Mack covering the song but with a Christmas theme to make Billie Mack's big comeback.