Elliot Gant (left) and his brother Marty.

Elliot Gant, the cofounder of Gant, the preppy shirtmaker that traces its roots to New Haven, Conn., in 1949, died on Saturday in Boca Raton, Fla. He was 89.

Gant was born in Brooklyn, N.Y., in 1926 and raised in New Haven. He was the son of Bernard Gant, who Americanized his name from Berl Gantmacher, a Jewish Russian immigrant who worked in New York’s garment industry on the Lower East Side. With his partner Morris Shapiro, Bernard Gant founded the Brooklyn-based Par-Ex Shirt Co., which made shirts for Brooks Brothers and others. In 1927, Par-Ex relocated to New Haven.

It was here that Elliot and his brother Marty got their first taste of the business, sweeping floors and fusing collars at the company’s shirt factory.

They took a break from the business to serve in the Army during World War II. Upon returning home, they convinced their father to exit the shirt contracting business and create shirts under their own label, and in April 1949, Gant was formed.

In the years that followed, Gant helped define the smart-yet-casual fashion that was sweeping the country. The brothers started experimenting with shirts in different fabrics and colors, and added more styles. They embraced their roots, changing the name of the brand to Gant of New Haven in 1954 and filling the Yale Co-op store on campus with its button-down shirts.

Elliot and his brother are credited with perfecting the perfect roll collar, the locker loop on the back of the shirt, the box pleat, the back-collar button and the neck button. Elliot is said to have invented the button tab to ensure that the tie tucked into the shirt’s roll, a look that soon became synonymous with the East Coast University look and won him an Esquire Fashion Design Award in 1963 in the category of men’s dress shirt.

But the brothers also stayed up-to-date on fashion trends and during the Sixties, they prohibited their sales staff from wearing white shirts at work, pushing instead the madras, tartans and candy-stripe colors they had begun to produce. The company was now known as Gant Shirtmakers.

They expanded into women’s wear shortly before the company was sold in 1968 to Consolidated Foods, but Elliot and Marty stayed on to run the business, expanding into sportswear in 1971. Knit shirts, including the rugby, were among the offerings and a subbrand was created in 1974 called the Rugger. Trousers and accessories were offered in 1981.

The brand changed hands several times, and Gant became a subsidiary of The Palm Beach Co. in 1979. In the early Eighties, Pyramid Sportswear of Sweden acquired the rights to design and market the Gant brand outside the States, turning it into a global brand.

Elliot is believed to have left the business in the Seventies.

In 1995, Phillips-Van Heusen acquired Gant in the U.S. from Crystal Brands Inc. of Connecticut. Gant was sold in 1999 to Pyramid Sportswear of Sweden, in which PVH held a 25 percent stake. Pyramid became Gant Pyramid AB and in 2006, the company went public on the Stockholm Stock Exchange. It was delisted later that year when it was bought by its present owner, Maus Frères.

Patrik Nilsson, chief executive officer of Gant, said: “Today we received the information about the passing of Elliot Gant, the sole remaining founder of the Gant brand. Elliot Gant was instrumental in establishing Gant, and together with his brother Marty Gant and father Bernard Gantmacher, he revolutionized the global men’s wear market by their expertise in shirtmaking, innovation and sense of style.

“While we are deeply sorry to hear about his passing, Elliot Gant, his brother and their father will remain with us in our everyday work through our values — passion, authenticity and innovation.”

Elliot Gant is survived by his wife, Ina (Romanoff) Gant; daughter, Carol Gant Leventhal; and son, Bernard Gant, as well as five grandchildren and one great-grandchild.