Oleg Cassini was a fashion designer who was born in Italy in 1913. He is best known for designing the wardrobe of Jacqueline Kennedy during her time as First Lady of the United States. He also designed for Hollywood stars such as Grace Kelly and Marilyn Monroe. Cassini was part of a group of designers, including Pierre Balmain, Hubert de Givenchy, and Christian Dior, who revolutionized the fashion industry in the 1950s and 1960s.