Barbra Streisand and Omar Sharif had an affair that lasted for the duration of the production. This would contribute to the end of her marriage to Elliott Gould. William Wyler, who knew about the affair, tried to channel their real-life chemistry into their performances.
Barbra Streisand was, at the time of the film's release, a voting member of AMPAS. When she found she was nominated, she, like any member nominated, voted for herself. If she hadn't, she wouldn't have tied with Katharine Hepburn for the year's Best Actress Oscar.
During the "My Man" number, William Wyler had Omar Sharif stand behind a nearby curtain and talk to Barbra Streisand between takes. Their affair was ending as the shoot came to an end, and Wyler knew that Sharif's presence would have an effect on her performance.
William Wyler was hired to replace Sidney Lumet as director. Lumet left the picture over differences with producer Ray Stark and star Barbra Streisand. Wyler originally declined the offer, because he was deaf in one ear and said he couldn't do a musical, but reconsidered after meeting Streisand.
The original Broadway production of "Funny Girl" opened at the Winter Garden Theater on March 26, 1964, ran for 1348 performances and was nominated for the 1964 Tony Awards for the Best Musical and Score. Barbra Streisand and Kay Medford reprise their roles in the movie and were both nominated for Tony Awards.
A publicity photo of Omar Sharif and Barbra Streisand kissing was released to the newspapers. With the emotions of the Six Day War still running high, the Egyptian press began a campaign to get Sharif's citizenship revoked over the kiss. The Egyptian headline read: "Omar Kisses Barbra, Egypt Angry." When asked to respond to the controversy, Streisand tried to make light of it. "Egypt angry!" she said. "You should hear what my Aunt Sarah said!"
According to some reports, Barbra Streisand was constantly late to the set, would ask to re-shoot scenes that were already done and try to control every aspect of the production from the lighting design to what sort of shot was needed to who did her hair.
At the wrap party William Wyler gave Barbra Streisand a director's megaphone in mock recognition of her devotion to every aspect of filmmaking including directing." Streisand gave Wyler an 18th century gold watch inscribed "TO MAKE UP FOR LOST TIME."
"The Swan" was written especially for this movie. The original number, "Rat-a-Tat-Tat", was deemed too dated (though appropriate for the setting of the show). Fanny Brice did a similar act dressed in a similar costume complete with a huntsman carrying a bow and arrow in the movie Be Yourself! (1930).
Production Designer Gene Callahan performed a cameo role as the tugboat captain. Gene's physical build and appearance (a distinctive beard) often had him cast by his film's director in a small cameo role. Like Alfred Hitchcock, if Gene liked the producer and director, he would agree to perform in the film, otherwise he would decline the proposal. Producer Ray Stark and Gene Callahan were always on the set during filming. Ray made Gene agree to perform the tugboat captain while the scene was filmed at sea to keep Gene available on the set.