Oscar de la Renta: Acclaimed fashion designer known as 'The Sultan of Suave' who dressed US First Ladies from Kennedy to Obama

"The most important thing in fashion is to have the memory of a mosquito," Oscar de la Renta told Gotham magazine. "Don't ever look back. Always look forward. You are only as good as your last collection." Known as "The Sultan of Suave", De la Renta was elegance personified, dressed impeccably, smelling beautifully, living a luxurious existence alien to mere mortals; the key to De la Renta was not his expensive aura but his charismatic character. Elizabeth Musmanno, President of the Fragrance Foundation, who travelled extensively with De la Renta in the 1990s, told the New York Post, "He would laugh. He would cry. He would sing. He was the master at the art of conversation.'

De la Renta's disarming charm was legendary. During a career which spanned more than half a century he dressed Hollywood celebrities, social A-listers and a succession of First Ladies which began with Jacqueline Kennedy and ended with Michelle Obama. In between there was Nancy Reagan, Betty Ford, Laura Bush and Hillary Clinton. In each case he wasn't simply their couturier of choice but the kind of friend close enough to deliver deadpan criticism. "I told her a while back she should cut her hair," he said of Clinton, who wore his dark crimson velvet dress on the cover of American Vogue. "He's been working for 20 years to turn me into a fashion icon," she said.

His frankness occasionally caused ripples. When he commented publicly about Michelle Obama's wardrobe to meet the Queen at Buckingham Palace he was snubbed. But eventually he smoothed the way for a sartorial entrée. "I would love to dress Mrs Obama " he told CBS. "I think she's a very stylish lady. " She was dressed in De la Renta at the White House Fashion Education Workshop she recently hosted.

Born in Santo Domingo in the Dominican Republic, with six older sisters, he was surrounded by females from an early age. The family business was insurance and it was assumed he would follow suit. Already with his eye on fashion, he had other ideas. With his mother's support he attended art school and at 15 was doing life drawing. His mother died of multiple sclerosis. He tried his hand at fashion illustrations and landed a job at Balenciaga's Madrid boutique via a friend.

Chosen as an unknown to make the "coming out " dress for the daughter of the American ambassador to Spain, De la Renta had a Life cover story by the time he was 19. In 1961 he went to work with Antonio del Castillo at Lanvin in Paris. Sensing that the future of fashion was in ready-to-wear rather than couture, De la Renta arrived in America in 1963.

It was standard practice for the department store – not the designer – to have their name on the garment, but De la Renta was one of the new breed of designers who changed that. Before long he had met the cosmetics guru, Elizabeth Arden, in New York and was advised by Diana Vreeland to take a post with her because it would be a quicker way to make his name. By 1965 he had joined Jane Derby, a Seventh Avenue organisation, taking over when Derby died.

De la Renta formed his own company in 1967. He cited Coco Chanel as the designer he most admired. "She really created the modern woman of today, " he said. "She was the most creative and innovative designer of the 20th century. In common with the legends of fashion design – Givenchy, Valentino, Balenciaga – De la Renta was the complete package. His style was never just about clothes. Elegant dressing. Chic houses. Beautiful surroundings. Delicious cuisine. The garden of his Connecticut country house was renowned for its taste. "I have made so many mistakes with the garden, " he said. "It's like fashion. Every time you plant something you learn, and it's different. "

Gregarious, and admitting that his Achilles' heel was that he wasn't comfortable being alone, De la Renta preferred the workroom to his office. Since the early days he had grasped that the key to success was continual reinvention. In the 1970s he attracted a new customer base which included Lauren Hutton, Liza Minnelli and Ali McGraw. Fast-forward to the 21st century, and De la Renta was being worn by Cameron Diaz, Penelope Cruz, Gwyneth Paltrow and Nicole Kidman.

Continually socialising with America's elite, he was accompanied by Oprah Winfrey to the Met Ball in 2010. His most recent triumph was creating the wedding dress for George Clooney's wife, Amal Alamuddin, for her Venice wedding. "George and I wanted a wedding that was romantic and elegant, " Alamuddin told American Vogue. "Meeting Oscar made the design process all the more magical, as he is so warm and such a gentleman."

With a rumoured intervention from American Vogue's Anna Wintour, De la Renta gave John Galliano the opportunity to re-engage with international fashion following the drunken, antisemitic rant which had ended his tenure at Dior and made him persona non grata. "John is one of the great talents of our times, " De la Renta told Vanity Fair. "It's always great to have another eye challenging you and we had a wonderful time working together. If you ask me the question, would you like to have him again? Yes."

Apart from his talent to create delicious dresses, Oscar De la Renta, who also founded the Casa del Niño orphanage in La Romana in the Dominican Republic, will be remembered for his humanity, humour and generosity.

Oscar Aristides Renta Fiallo (Oscar de la Renta), fashion designer: born Santo Domingo, Dominican Republic 22 July 1932; married 1967 Françoise de Langlade (died 1983), 1989 Annette Engelhard; died Kent, Connecticut 20 October 2014.