If there is one thing I feel smug about, it is this: I have no interest in celebrities. Okay, I bought the Charles and Camilla wedding issue of Hello! in Waitrose, but generally nothing renders me comatose faster than covers of Vanity Fair or headlines about Kate Moss’s future. So, with that little molehill of intellectual superiority established, I confess that I’ve spent the morning in the lambing shed with a thermos of mint tea, a two-day-old newspaper, and a reverie of memory as I studied the photograph of Jackie Kennedy. She is leaving her married home for the gala ball the evening before the inauguration. Snow is falling, the young president elect is behind her, and she is wearing the ivory silk satin dress that will establish her in the national consciousness as the young, hopeful bride of the nation.

The picture of the regal dress illustrates the obituary of its designer, Oleg Cassini. Born in 1913 in Paris to aristocratic Russian parents who later fled the revolution, once married to Hollywood actress Gene Tierney and briefly engaged to Grace Kelly, it was Cassini who persuaded Mrs Kennedy to allow him to create all of her formal wear; Cassini who understood perfectly her love of Givenchy, her preference for simple, bold lines, and the understated elegance that would become the ‘Jackie look’. During the 1,000 days of the Kennedy presidency, he created 300 outfits for her.

What astonishes me, especially as I get older, is that the woman in the ivory dress was only 31 years old. That seven weeks earlier she had given birth to John Jr. That she had helped plan the programme for that evening that included a fanfare by Leonard Bernstein, a reading by Eleanor Roosevelt from Lincoln’s writings, performances by Laurence Olivier and Ella Fitzgerald.

And then the inauguration itself. Remember the fawn coloured wool coat with the sable collar, the fur-lined boots? (‘The other ladies wore fur coats, and they looked like bears,’ observed Cassini.) The First Lady: elegant, modern, smart. At her instigation, the poet Robert Frost recited his poem The Outright Gift, because, as one reporter put it, the Kennedys, ‘unlike most Americans, find poetry nourishing, rather than frightening.’

Back then, I don’t remember being impressed by Jackie Kennedy’s intelligence, her sense of history. I remember the clothes, a memory backed up by my mother’s wardrobe of streamlined dresses and suits, including a pillbox hat by Halston that I wore 30 years later at my son’s christening.

Even now, every few years, I buy a dress, a suit, a boucle jacket, clothes that make me look more like an air hostess than the graceful, athletic woman who is still a potent part of my visual memory. I reckon these clothes are about a yearning for another age, an age when the leaders of a country welcomed Nobel Prize winners more than football players. When dinners with carefully chosen food and wine, cellists playing Bach suites, and beautiful clothes were not seen as decadent, but as uplifting. Don’t worry. I know the other side of Camelot. No stone left unturned there. But I’m grateful that the slain president’s widow, age 33 when she organised her husband’s funeral, never wrote her side of the story, never appeared on Oprah.

After she left the White House, the hats and the dresses with their matching coats were consigned to the cupboard of history. Her clothes became softer, freer, But she never cast off her innate sense of dignity and its twin, a passion for privacy traits that now seem as delicate and beautiful as the ivory satin of an Oleg Cassini gown.

This article first appeared in Country Life magazine on March 30, 2006.