Ziegfeld Girls were the showgirls from Florenz Ziegfeld's theater shows known as the Ziegfeld Follies, which were based on the Folies Bergère of Paris.
This set features the portraits of Alfred Cheney Johnston, who is known for taking portraits of the Ziegfield girls as well as other actors/actresses of the 1920s/1930s. If you are interested in the stories of these girls or want to see more portraits of Ziegfield girls, you should get Jazz Age Beauties: The Lost Collection of Ziegfeld Photographer Alfred Cheney Johnston from Amazon.
You should also check out First Decade of Decadence by Esteban Palazuelos and Vanity Fair 1953 Photography by Mark Shaw. You can definitely see the inspiration they drew from Johnston's photos.