In an interview with The Britain's 'Telegraph' in April 2015, Andrew Morton told Angela Wintle, "I was earning quite a lot before 'Diana: Her True Story' came along in 1992, but obviously it transformed my reputation and finances. It enabled my then wife and I to sell our house in Muswell Hill and move to the leafy area of Highgate in north London. But it was a high-risk venture.
"The book trade didn’t think the world was interested in another Diana publication, so early subscriptions were paltry and only 18,000 copies were printed. We subsequently lost sales because there weren’t enough books to go around . . . The book went on to sell about 7 million copies in 80 countries, and I made more than £1m over several years. In 1997, the commemorative edition topped the best-seller lists again, selling 180,000 copies in the first week. The first book is still in the Top 20 for Kindle non-fiction Royal best-sellers and earns me a few hundred pounds a year, which is marvelous when you think it's 23 years old."
'Diana: Her True Story' was made into a TV mini-series in 1993 starring Serena Scott Thomas and David Threlfall. At the time, Ann Robson recognized, "It (the book) was a major topic of conversation throughout England and now (in August 1992) in North America, where it has made the best-seller lists." In Britain, the mini-series 'Diana: Her True Story' was shown on Valentine's Day. "The opener earned the highest ratings achieved by Sky Television in the company's (at the time) 3-year history," it was reported. In the New World, the mini-series was shown in April 1993.
Producer Martin Poll told 'The Washington Post' in 1993, "In addition to Andrew's book, there was a lot of research, I had people connected with the Royals – and I’m not talking about some backstairs butler or a disgruntled secretary – checking the script. I told them, 'I’m going to attempt to do this objectively, and I can't do this if I don't have the information. I need to know where they sit when they come into a room, or around a table, how they dress and so forth.'"
In December 1993, Diana made the announcement, "At the end of this year, when I've completed my diary of official engagements, I will be reducing the extent of the public life I've lead so far." Her Majesty's former press secretary Dickie Arbiter remembered, "I remember extremely well when Diana announced that she was going to withdraw from public life. I think she reached the crossroads and she needed time to reflect." In 'Diana: Her True Story', Andrew mentioned, "Fate has taken her on a different journey, a route where the Monarchy is secondary to her true vocation. That road leads … to her work for the sick, the dying and the distressed (the "battered this, battered that")."
Back in June 1992, Andrew told the 'Chicago Tribune', "My first priority was to make sure the book was accurate and could withstand all kinds of scrutiny. And this book has withstood the most intense and searching scrutiny of any book probably in the history of Royal watching."
Andrew also told Jay Bobbin of 'Tribune Media Services' at the time, "The reason this book has been taken seriously – not just in America, but also by a very skeptical British establishment – is the very fact that it is authentic. The people who spoke to me are demonstrably friends and family of the Princess, and they did not just run for the hills when the book came out, but stood by its integrity."
"The whole purpose of the book was to write her true story, from her perspective," Andrew pointed out. "Prince Charles has his true story to tell, and it will be a very different one than his wife's." Martin Poll admitted, "I don't profess that I'm a Anglophile, but after the research that had been done for 'The Lion in Winter', the interest continued for me . . . Andrew's point of view and information in the book, I thought, was imperative to making a dramatization which would have integrity. We're not interested in making something sensational or sleazy, and Andrew has written over 10 books (up until that time) about the Royal Family. They're very carefully researched."
In March 2004, some 16 million plus Americans (aged 18-49) were counted watching a "worldwide exclusive" on NBC 'Princess Diana: The Secret Tapes' to see "never-before-heard 6 audio tapes" of Diana recording for the Andrew Morton's blockbusting book.