The mum-of-two now campaigns for her Children in Crisis worldwide charity and works on historical documentaries and films that draw on her deep interest in Victorian history.
Mills & Boon, the longstanding titan of bodice-busting fiction, has announced it is to publish Sarah Ferguson's debut work of adult fiction in August after she delved into her own family history in search of inspiration for a suitably epic tale of romance to scale the best-seller lists.
Kaye has written more than 50 novels for Mills & Boon set across the ages and her books and novellas have sold more than 1.5 million copies in over 20 countries.
Born Sarah Ferguson and nicknamed Fergie by the press, she once confessed: "I was hopeless from the start. they could never make me the flawless princess".
But although her parents, the Duke and Duchess of Buccleuch, were close friends with Queen Victoria and Prince Albert, the Duchess was unable to source much information.
"The story itself is based on one of my ancestors and I've spent the last couple of years doing my own research into my family history with the help of the royal archives", she wrote on Instagram.
The story will include some real people and events and also draw on the duchess's own experiences but she said "my imagination took over".
She thoroughly enjoyed the experience and is already working on her second.
"I created a friendship between my heroine and Princess Louise, Queen Victoria's sixth child, and I drew on many parallels from my life for Lady Margaret's journey".
Mills & Boon described the story as a "fascinating journey of a woman, born into the higher echelons of society, who desires to break the mould, follow her internal compass (her heart) and discover her raison d'être - and falling in love along the way".
In a promotional video posted Wednesday on her Twitter account, the former Sarah Ferguson said the novel, titled "Her Heart for a Compass", is set in the Victorian era and is "about daring to follow your heart against the odds".
She has been reading children's books throughout the pandemic on her YouTube channel, Storytime with Fergie and Friends.
Sarah added: "I have long held a passion for historical research and telling the stories of strong women in history through film and television".
"I am proud to bring my personal brand of historical fiction to the publishing world".
Sarah, Duchess of York has some exciting news!
Lisa Milton, executive publisher for Mills & Boon, described Fergie's novel as a "brilliant sweeping story".
As well as a number of children's books, including the successful Little Red and Budgie the Little Helicopter series', the Duchess has written two memoirs, My Story and Finding Sarah.