At the beginning of the "Bring On The Beautiful Girls" number, several older women are shown; these are women who actually appeared in the original Ziegfeld Follies on stage.
The horse ridden by Lucille Ball is Zorro (1949)'s Silver. When Life magazine showed a photo of Silver in his pink feathers and bows with the headline 'Silver is a Sissy', the horse's trainer threatened to sue MGM for defamation of Silver's character.
The machine producing the bubbles for the finale was responsible for one of the greatest filming fiascoes in movie history. On the first day of filming the finale, the gas produced by the bubbles caused Vincente Minnelli's cameraman to faint on top of a forty foot lift. While Minnelli struggled to stop his cameraman from falling, the bubbles continued to pour from the machine to such an extent that the soundstage was flooded with bubbles, and no one could get close enough to turn the machine off. Eventually, the fire brigade was called to turn stop it. Afterwards, teams of workers used large rackets to keep them under control, but the gas from the bubbles remained a constant hazard, and between each take Minnelli would order the soundstage's doors open so the cast and crew could breathe. James Melton filmed with a wet handkerchief in his mouth to protect his voice. Fred Astaire and Lucille Bremer's dance was removed completely, since in every take of them, the bubbles obscured part of their face.
Lucille Ball, who stars in this production based on Florenz Ziegfeld Jr.'s legendary shows, was fired by Ziegfeld from his production, Rio Rita, in the 1930s.
Many people have wondered why the "Limehouse Blues" sequence was done with a Chinese background. The British discovered that giving sailors lime juice prevented scurvy, a disease caused by a lack of vitamin C. To provide enough juice for the navy, they built a large building on the northern bank of the River Thames in East London, England and staffed it with hundreds of imported Chinese laborers to extract the juice from shiploads of limes. A "Chinatown" built up around the limehouse (as it was called) to provide housing for the workers. To this day, the British are referred to as "Limeys" by North Americans because of their use of the lime juice.