The pillbox hat, the cloth coat, the Nehru jacket and the brightly-colored men's shirt were all looks popularized by the Paris-bred Russian designer, who settled in the U.S. in the 1930s. Mr. Cassini was one of the major post-World War II celebrity designers: He had taste, wasn't afraid of TV cameras ("The Tonight Show," "The Mike Douglas Show") and had a reputation as a playboy.

The film actress Gene Tierney was his wife — they were married and divorced twice, and had two daughters — and he was enlisted in the 1940s and '50s to design her costumes in such films as "The Ghost and Mrs. Muir" and "The Razor's Edge." Mr. Cassini reportedly had a long romance with Grace Kelly before she married the Prince of Monaco.

According to the Internet Broadway Database, Mr. Cassini had four Broadway credits: Garson Kanin's 1962 play Come on Strong starring Carroll Baker ("Miss Baker's Wardrobe by Oleg Cassini"); the 1960 Ira Levin play Critic's Choice ("costumes Provided by Oleg Cassini"); Fay and Michael Kanin's 1954 comedy His and Hers starring Celeste Holm ("Miss Holm's clothes by Oleg Cassini"); and the 1948 musical As the Girls Go ("costume design by Oleg Cassini").