Stirling is the eldest son of William Joseph Stirling, of Keir (9 May 1911 - 1983) and wife (m. 22 November 1940) Susan Rachel Bligh (12 August 1916 - 1983), and a nephew of Colonel Sir David Stirling, OBE, DSO, who was the founder of the Special Air Service, and both are descendants of King Charles II of Scotland and England. His sister Hannah is married to Robert Michael James Gascoyne-Cecil, 7th Marquess of Salisbury.
Stirling's first wife was Charmian Rachel Montagu Douglas Scott (18 July 1942 – 5 April 2009). They married on 11 November 1964 and were divorced in 1977. She was the niece of Princess Alice, Duchess of Gloucester and the granddaughter of the John Montagu Douglas Scott, 7th Duke of Buccleuch. The couple had two sons, William Rory Alexander Stirling, born on 15 December 1965, and Ludovic David Stirling, born on 29 April 1967.
Stirling was married to actress Dame Diana Rigg for eight years, from 1982 to 1990; their only child is the actress Rachael Stirling, who was born in 1977. Their marriage ended in a 1990 divorce after Stirling had an affair with actress Joely Richardson.
Scottish Voice political party
On 4 January 2007, BBC News reported that Stirling had begun setting up a new political party aiming to improve standards at the Scottish Parliament in order "to make Scottish politics work for the disillusioned majority," and will "also put defending the Union at the heart of its policy." The right-wing party, known as Scottish Voice, was formally launched in February 2007, and stood in the Scottish Elections of 2007, but drew a low vote and failed to gain any seats.
Further coverage and analysis published on 5 January 2007 was provided by The Herald  and The Scotsman. The party was backed by an unnamed group of like-minded people, including the millionaire Inverness businessman Robert Mcleod Hotchkiss, opposed to the breakup of the United Kingdom. Due to a breach in security, information and documents were leaked in advance of the launch.
In April 2012, Stirling announced that he was winding-up the party.
- "Diana Rigg: Her Story". Telegraph.co.UK. Archived from the original on 3 August 2008. Retrieved 8 July 2008.
- "Millionaire plans political party". BBC News. 4 January 2007. Retrieved 25 April 2010.
- Macdonell, Hamish (5 January 2007). "Millionaire maverick plans 'what about us' party". The Scotsman (Edinburgh).
- Walker, Tim (24 April 2012). "'Archie Stirling quits Scottish politics for good' - Daily Telegraph". The Daily Telegraph (London). Retrieved 24 April 2012.