The three day celebration of the printed word is at the stately home from Friday to Sunday October 5 to 7.
Politicians Paddy Ashdown and Alan Johnson will be speaking along with Prue Leith, judge on The Great British Bake Off.
Downton Abbey creator Julian Fellowes takes a break from writing the recently announced movie adaptation of the ITV drama to speak at the festival.
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Historian Dan Snow as well as best selling novelists Bernard Cornwell and Alexander McCall Smith are also due to feature at the festival.
Earl Spencer - owner of Althorp and founder of the Althorp Literary Festival - is also a bestselling historian, writing as Charles Spencer. He said he was delighted by the line up.
He said: “The Althorp Literary Festival is unique in the way it so warmly welcomes authors and audiences alike, for I have to say it’s an honour to have a line-up such as the one we have this coming October.
“Many of our authors now approach me to see if they can come, which is really heartening.”
It is a level of enthusiasm which is also shared by some of the authors coming along to the festival.
Award-winning Dan Jones, author of international bestsellers including The Templars, says: “With brilliant line-ups of speakers in one of Britain’s most stunning venues, Althorp Literary Festival is simply magnificent - no other word will do.
“Appearing on the bill is a pleasure and a privilege and I can’t wait to return this October”.
Bernard Cornwell, author of multi-million-selling historical novels, including the Sharpe series, is similarly enthusiastic about his return to the Althorp Literary Festival this October:
He said: “Books and Althorp form an idyllic blend of beauty, wit and wisdom. It’s by far my favourite festival!”
Althorp House – one of England’s most beautiful private, historic houses - provides an idyllic backdrop for the three-day Festival.
The event also boasts a wide range of pop-up retail outlets, live performances and a variety of curated food and drink vendors.
Over the past fourteen years, the Festival has attracted more than 300 best-selling and critically acclaimed authors, outspoken politicians, sporting heroes, comedians and stars of stage and screen to share their stories with the public.
These include Bill Bryson, Boris Johnson, Helen Fielding, Jo Malone, Judy Murray, Darcey Bussell, Sir Tom Stoppard, Twiggy, Sebastian Faulks, Jung Chang and Michael Palin.
Althorp House is one of the most beautiful stately homes in England, surrounded by 550 acres of idyllic parkland.
Historic home to the Spencer family for over 500 years, Althorp House and Park is a glorious spot to spend a day being inspired.
A thriving hub for lavish entertainment, Althorp plays host to a number of exclusive events each year, including The Althorp Food and Drink Festival in May as well as the literary festival.
Tickets for the show are likely to be highly in demand so people have been advised to book tickets as soon as possible.
Individual sessions cost £16 or £12.50 for the shorter lunchtime sessions.
For further informatiom about the literary festival including the full line up or to book tickets for any of the talks in advance visit www.spencerofalthorp.com.