Writer and creator Anthony Horowitz based the character of Sam Stewart on his childhood nanny and governess Norah Fitzgerald, who had been a WAAF driver during World War II, and used to tell Horowitz stories of her wartime experiences and exploits.

Looking for a replacement for its successful Inspector Morse (1987) series, ITV solicited ideas and picked Foyle's War (2002) out of 300 submissions.

To the considerable mystification and annoyance of Anthony Horowitz (writer) and the cast, Simon Shaps, former Director of Television for ITV, who only stayed in the job for eighteen months, announced in 2007 that he would kill off this well-respected and lucrative series after making one final season of episodes. Horowitz had to abandon several scripts for episodes set in 1944, and jump forwards to episodes covering the end of the war in 1945. However in February 2009 it was announced that this decision had been reversed now Shaps had left his TV executive role, and three more episodes would be filmed. Foyle's War: The Russian House (2010), set in peace-time, was the first of these episodes.

Detective Chief Superintendent Christopher Foyle was voted as the nation's favorite detective in 2011.

In most of the episodes during the war years, most people on the street are seen carrying small cardboard boxes slung over the shoulder on a string. These are gas masks, which were issued to every man, woman and child in Britain.

Michael Kitchen and some of the guest cast had starred in the James Bond films. Kitchen played Bill Tanner during the Pierce Brosnan era.

Andrew's "Spitfire" squadron was shown in Foyle's War: Enemy Fire (2004). But most of the planes shown are Hurricanes, not Spitfires. That can be told by the engine exhausts.

Each episode of this series requires around five weeks to film.

Anthony Horowitz's working title for the series was "The Blitz Detective".

The series was nominated for the 2004 BAFTA Best Drama Series award.

In a newspaper article and an interview accompanying the series-one DVD set, Anthony Horowitz explained that he was seeking a name which evoked the early 1940s. He thought of Foyles bookshop in London's Charing Cross Road, once known for its archaic business practices and its owner, Christina Foyle; Christopher was the nearest male name to Christina. After Christina Foyle's death, control of Foyles passed in 1999 to her nephew Christopher. Christopher Foyle made a cameo appearance in the episode "Foyle's War: Bad Blood (2006)", although his scene was cut from PBS airings in the US.

The series is notable for its attention to historical detail, and the drama is frequently moved along by historical events of the Second World War. Anthony Horowitz considered that to honour the veterans of the war it was important to get the details correct.

As the series progressed, Anthony Horowitz became more interested in the "murder mystery" format than the portrayal of history and exploration of the Home Front. However, the Imperial War Museum is credited in an advisory capacity in some episodes.

The black car in which Sam Stewart drives DCS Foyle around is an authentic Riley Kestrel, noted for its so-called "suicide" doors that opened towards the rear.

The building used to film exterior shots of the "new" police headquarters in Foyle's War: Killing Time (2010) is adjacent to the one used for the exterior shots of the Sunshine Dessert Company, in The Fall and Rise of Reginald Perrin (1976). The buildings are located on Telford Way, in Acton, London, UK.

David Tennant appeared opposite Sophia Myles in Foyle's War: A Lesson in Murder (2002). He was Sophia's boyfriend at the time and they would work together again on Doctor Who (2005). The couple broke up in 2007.

After five series, Foyle's War was abruptly cancelled by ITV director of programmes Simon Shaps. This forced Anthony Horowitz to discard scripts set during most of 1943 and 1944, resulting in time jumps of nine months to a year between episodes; previous series had gaps of a month at most.

Foyle's War was nominated in the Best Production Design category for the 2003 BAFTA Television Awards, and won a Lew Grade Award for Best Entertainment Programme that year.

Foyle's War is a British detective drama television series set during (and shortly after) the Second World War, created by Midsomer Murders (1997) screenwriter and author Anthony Horowitz.

ITV director of programmes Simon Shaps cancelled Foyle's War in 2007, but complaints and public demand prompted Peter Fincham (Shaps' replacement) to revive the programme after good ratings for 2008's fifth series.

The final episode was broadcast on 18 January 2015, after eight series.

Series seven was filmed in Ireland and London from late August to December 2012, and was broadcast in the UK in March and April 2013.

Series eight, three two-hour episodes, aired in the UK in January 2015.

The series began broadcasting on ITV in October 2002.

On 9 April 2008, ITV announced that it was negotiating with Anthony Horowitz and Greenlit Productions to revive the series and continue Foyle's adventures beyond VE Day.

In April 2008, the presumed final episode, "Foyle's War: All Clear (2008)" (during which the end of the war is announced) was broadcast.

Will Keen (Alan Deakin), Joseph Kloska (DC Perkins) & David Yelland (Sir Charles Devereaux) also worked together on The Crown (2016) as Michael Adeane, Porchey & Commander Vyner respectively.

Series six began filming in February 2009 and premiered on UK television on 11 April 2010.

The series began broadcasting in Africa in 2009 on the pay service DStv (broadcast from South Africa) on the Universal Channel.

Aired in Australia on the ABC, with repeats on the Seven Network.

Broadcast in Ontario on TV Ontario.

Broadcast in Finland on YLE1; series seven and eight broadcast in 2015-2016.

There is a real-life parallel to Christopher Foyle in the person of Charles Banks, who spent 33 years with the police, rising to the rank of sergeant and then patrol inspector, and then putting in another eleven years as a civilian. Like Foyle, he also wrote a book which covered the war years in Hastings as well as the history of the area going back a century: The History of the Hastings County Borough Police From 1935 to 1967.

During the war Hastings survived 85 air attacks, 14 small bombs, 12 oil incendiaries, 750 incendiaries, and 15 flying bombs. This resulted in the loss of 154 lives, with 260 serious injuries and 439 minor injuries.763 structures were destroyed and 14,818 properties were damaged.