Tassell (pronounced Tass-SELL) designed clothes that Jackie Kennedy wore as first lady on a highly publicized goodwill tour of India in 1962.
After serving in the Army, Tassell was studying painting in New York City in the late 1940s when he took a job in the advertising and display department for Hattie Carnegie, a pioneer in the fashion design world who was well known for both custom-made and high-end ready-to-wear clothes.
In 1962, the year after he won the Coty Award, Jacqueline Kennedy was photographed in India wearing a shimmering yellow silk Tassell dress while riding an elephant.
The dress was among the Tassell designs showcased in a 2001 exhibit at New York's Metropolitan Museum of Art called "Jacqueline Kennedy: The White House Years."
His clientele desired what he called "a subtle form of chic" — coats, dresses and evening wear in fine silks and gabardines and subdued colors, with simple lines that skimmed the body and price tags that sometimes exceeded those for a car.
Once described as a "brunet Harpo Marx" because of his curly hair, Tassell earned a bit part as a cabaret patron in director Woody Allen's 1980 movie "Stardust Memories."