Douglas Emerson asked to be released from his role as Scott Scanlon because he'd lost interest in acting. Since then, he has retired from acting, spent several years in the U.S. Air Force, and started a family.
The character of Dylan was only supposed to appear in one or two episodes. Fox executives weren't sold on the fictional character or Luke Perry's acting ability. Aaron Spelling used his own funds to pay Perry's salary during those initial episodes, and the positive audience response led Fox to approve his addition to the regular cast.
In 2016, Gabrielle Carteris became president of SAG-AFTRA (the Screen Actors Guild and the American Federation of Television and Radio Artists). As one of her first causes as SAG president, Carteris, who was often singled out for ridicule because she was over a decade older than most high school graduates when Beverly Hills, 90210 (1990) started, took up California Bill AB 1687, which would require entertainment websites and databases to remove actors' ages if they request it. When the bill passed, Carteris released a statement saying that the new law would help prevent age-based discrimination in Hollywood and "career damage caused by the publication of performers' dates of birth on online subscription websites used for casting like IMDb."
The show had many changes after the pilot. The Walsh house changed to a different building, which explains why the scenery behind James Eckhouse in the re-shot pilot scenes matches the Walsh house used in the remaining 10 years of the series, but not the house used only in the pilot. Brandon's car changed from a Chevy Chevette to a 1978 Mercury Cougar, called "Mondale". Luke Perry is first featured in the second episode. The building for "The Peach Pit" changed a few episodes into season one.
Although Valerie Malone mentions Brenda Walsh as a close family friend, Shannen Doherty and Tiffani Thiessen never appeared together in a scene. Thiessen was cast as a replacement after Doherty left. That was only explained as a reason for the relationship between the characters by including her on the show.
Luke Perry, who played Dylan McKay was the first from the main cast of the show to have tragically passed away from a massive stroke on March 4, 2019, at the age of 52. His family was by his side upon his passing.
Brandon's car was named after Walter Mondale, Minnesota's senior U.S. Senator during the late 1970's and early 1980's. He was the Democratic nominee for president in 1984, losing to incumbent Ronald Reagan.
Actors Vivica A. Fox, Djimon Hounsou, and Casper Van Dien made appearances on episodes of the show. Fox, played Brandon's interracial love interest, Hounsou played a bouncer and Van Dien was Steve's frat brother.