Donald Pleasence had actually been a Royal Air Force pilot in World War II, who was shot down, became a prisoner of war and was tortured by the Germans. When he kindly offered advice to the film's director John Sturges, he was politely asked to keep his "opinions" to himself. Later, when another star from the film informed John Sturges that Pleasence had actually been a RAF Officer in a World War II German POW Stalag camp, Sturges requested his technical advice and input on historical accuracy from that point forward.
During the climatic motorcycle chase, John Sturges allowed Steve McQueen to ride (in disguise) as one of the pursuing German soldiers, so that in the final sequence, through the magic of editing, he's actually chasing himself.
During production, Charles Bronson met and fell in love with David McCallum's wife, Jill Ireland, and he jokingly told McCallum he was going to steal her away from him. In 1967, Ireland and McCallum divorced, and she married Bronson.
Charles Bronson, who portrays the chief tunneler, brought his own expertise and experiences to the set: he had been a coal miner before turning to acting and gave director John Sturges advice on how to move the earth. As a result of his work in the coal mines, Bronson suffered from claustrophobia just as his character had.
One day, the police in the German town where the film was shot set up a speed trap near the set. Several members of the cast and crew were caught, including Steve McQueen. The Chief of Police told McQueen "Herr McQueen, we have caught several of your comrades today, but you have won the prize [for the highest speeding]." McQueen was arrested and briefly jailed.
Although Steve McQueen did his own motorcycle riding, there was one stunt he did not perform: the hair-raising 60-foot jump over a fence. This was done by McQueen's friend Bud Ekins, who was managing a Los Angeles-area motorcycle shop when recruited for the stunt. It was the beginning of a new career for Ekins, as he later doubled for McQueen in Bullitt (1968) and did much of the motorcycle riding on the television series CHiPs (1977).
Steve McQueen's character Hilts was based on amalgamation of several characters, including Major Dave Jones, a flight commander during Doolittle's Raid who made it to Europe and was shot down and captured and Colonel Jerry Sage, who was an OSS agent in the North African desert when he was captured. Col. Sage was able to don a flight jacket and pass as a flier otherwise he would have been executed as a spy. Another inspiration was probably Sqn Ldr Eric Foster who escaped no less than seven times from German prisoner-of-war camps.
During idle periods while The Great Escape (1963) was in production, all cast and crew members - from stars Steve McQueen and James Garner to production assistants and obscure food service workers - were asked to take thin, five-inch strings of black rubber and knot them around other thin strings of black rubber of enormous length. The finished results of all this knotting were the coils and fences of barbed wire seen throughout the film.
Paul Brickhill, who wrote the book from which the film is based, was piloting a Spitfire aircraft that was shot down over Tunisia in March 1943. He was taken to Stalag Luft III in Germany, where he assisted in the escape preparations.
The motorcycle that Hilts (Steve McQueen) rides is a cosmetically modified Triumph TR6 Trophy. Bud Ekins who actually performs the famous barbed wire leap stunt, was a Triumph dealer. Triumph was McQueen's favorite motorcycle marque. The motorcycle sidecar combination that crashes into a ditch is revealed to be a Triumph motorcycle, too. As is well known, these British motorcycle models were not in existence during the Second World War and their appearance is somewhat incongruous.
For the train sequences, a railroad engine was rented and two condemned cars were purchased and modified to house the camera equipment. Scenes were shot on the single rail line between Munich and Hamburg, and a railroad representative was on hand to advise the filmmakers when to pull aside to avoid hitting scheduled oncoming trains.
The real-life escape preparations involved 600 men working for well over a year. The escape did have the desired effect of diverting German resources, including a doubling of the number of guards after the Gestapo took over the camp from the Luftwaffe.
The medal that Colonel von Luger wears around his neck is the Pour le Merite, also known as the Blue Max. Originally a Prussian military honor, in the First World War it was automatically given to fighter pilots who shot down eight planes (later raised to sixteen). The Nazis replaced it with the Knight's Cross but it could still be worn by officers who'd won it before the Third Reich.
The character of von Luger was actually based on Friedrich von Lindeiner-Wildau. As with von Luger, the real commandant was an Oberst (Colonel), a general staff officer, and a holder of the "Blue Max" (Pour le Merite) medal. However, while the pictures on the wall of von Luger's office are of World War I flying units, von Lindeiner-Wildau earned his Blue Max in the East Africa campaigns in 1905-07 and served as an infantry officer before and during World War I. He retired from the Army in 1919 and only joined the Luftwaffe in 1937 at 'Hermann Goring''s personal invitation.
The film was shot entirely on location in Europe, with a complete camp resembling Stalag Luft III built near Munich, Germany. Exteriors for the escape sequences were shot in the Rhine Country and areas near the North Sea, and Steve McQueen's motorcycle scenes were filmed in Fussen (on the Austrian border) and the Alps. All interiors were filmed at the Bavaria Studio in Munich.
Richard Attenborough was an RAF air gunner/photographer who served in the RAF for three years unlike his character, based on Squadron Leader Roger Bushell who was a Spitfire Pilot in 92 Squadron in the early years of World War Two.
The newspaper that Ashley-Pitt (David McCallum) reads on the train is the 'Völkischer Beobachter', a real newspaper produced for 25 years by the National Socialist German Workers Party. It served as a propaganda sheet for the Nazis and helped bring Adolf Hitler to power. At its height, it had a circulation of approximately 1.4 million. The headline for the issue seen in the film translates roughly to "Day after day, the Soviets have high, bloody losses." Given that the escape in the film occurs in the summer of 1944, this too can be viewed as propaganda. The Nazis had transferred hundreds of thousands of troops to Normandy to stop the Allied advances after D-Day, allowing for the Soviet's to launch Operation Bagration on 22 June, which pushed the Nazis back into Poland by the beginning of 13 July and sparked the Warsaw uprising. In all, the Soviet advance caused German losses of approximately 670,000 dead, missing, wounded and sick, including 160,000 captured. Although the date of the escape is unclear, given the green pastures around the Alps that the escapees encounter, one can easily surmise that the newspaper was putting a positive spin on the battles in the east.
The song sung by Ives & McDonald on 4th July is "Wha [who] saw the 42nd?" Contrary to common belief it is not in Gaelic but (heavily accented) English. The 42nd Regiment of Foot was a Scottish regiment (the Black Watch) in the British army.
When the Bavaria Studio's backlot proved to be too small, the production team obtained permission from the German government to shoot in a national forest adjoining the studio. After the end of principal photography, the company restored (by reseeding) some 2,000 small pine trees that had been damaged in the course of shooting.
When celebrating the Fourth of July and pouring alcohol, Hilts (Steve McQueen) is thrown off by an ad-lib by Goff (Jud Taylor). While Hilts is drinking, Goff says, "No taxation without representation." McQueen jumps out of character and gives him a look (and mouths, "What?") The director must have signaled to "just go with it" and the scene continues. But it is an obvious ad-lib.
MacDonald (Intelligence) is based on George Harsh, a very good friend of Wally Floody (the real Tunnel King). They were both transferred to Belaria before the escape. Harsh was a very interesting character who was from the American south and had joined the RCAF as a tail-gunner. In the 1920s Harsh had committed murder and was sent to jail for life. A medical student, Harsh performed an appendectomy on a dying prisoner and saved his life. The governor of Georgia granted him a pardon and he was set free. After the war, he had personal problems as he was plagued by guilt over the crime he committed as a youth; on top of adjusting to life after fifteen years in captivity (12 years on the Georgia chain gang, followed by three years as POW). On Christmas Eve 1974, he did shoot himself but survived. A stroke soon after left him partially paralyzed. When that happened, Wally Floody and his wife brought him up to their Toronto home and looked after him. He eventually went to live -at his own urging- at the Veteran's Wing at the Sunnybrook Medical Centre. He died in January of 1980.
The film was shot on location in a German forest. To make room for the camp set, several trees had to be bulldozed. John Sturges had to show the West German Minister of the Interior his plans and, to get permission to bulldoze, had to promise to plant two seeds for every tree felled when production was over.
The real-life escape was on the night of 24 March 1944, and the ground was snow-covered. The German town near the prison camp, called Neustadt in the film, was really Sagan (now Zagan, Poland). Steve McQueen was born on March 24th.
The hooch-making scene in the film, where the Americans celebrated Independence Day, is believed to be based on the British creating an alcohol distillery for Christmas Day celebrations in 1943. Captain Guy Griffiths, a Royal Marine pilot in Stalag Luft III who produced forged documents for the escape, also produced a comical illustration of the scene which survives to this day. This painting, along with many others, forms the basis for a Special Exhibition on 'Griff' at the Royal Marines Museum (Southsea, England) running from Easter 2010.
In the scene following Hilts' theft of a German motorcycle, he rolls into a nearby town, and stopped by a police officer. He tells Hilts something in German, to which Hilts kicks him away and rides off. The officer asked Hilts for identification papers Hilts doesn't have.
Donald Pleasence's character was based partly on London-born John Cordwell, later a Chicago architect and then proprietor of the Red Lion Pub on the city's N. Lincoln Avenue. Cordwell died in 1999. Stories about him and the Red Lion are told from various points of view in the collection "Tales from the Red Lion" (Chicago: Twilight Tales, 2007, ISBN 0977985623).
There are seven different languages spoken or sung in the movie: English, German, French, Russian and one word in Spanish as well as two words of Latin "Lanius Nubicus" when Flight Lieutenant Blythe is describing the masked shrike or butcher bird in the forgery scene. There is also a song in Scottish Gaelic where Ives and MacDonald are singing in the 4th of July scene just before "Tom" is discovered.
Although the German airfield displays mainly North American AT-6 Texan trainers, it is feasible that this was authentic. The Germans did use the AT-6 in some numbers as advanced trainers, which they had sequestrated from the French in 1940.
Some aspects of the escape remained classified during production and were not revealed until well after. The inclusion of chocolate, coffee and cigarettes in Red Cross packages is well documented, as is their use to bribe Nazi guards. Other materials useful for escaping had to be kept secret and were not included in the novel or screenplay. Also not revealed until many years later was the fact that the prisoners actually built a fourth tunnel called "George."
The trivia items below may give away important plot points.
Whenever a prisoner attempting escape is told "good luck" by a fellow prisoner, the escape fails. Ironically, these are the same words that the German officer uses to capture Bartlett and MacDonald near the end of the film.
According to David McCallum, the barbed wire that Hilts (Steve McQueen) crashes into near the end of the film, which was actually made of rubber, was made by the cast and crew during their free time by tying small pieces of rubber around larger ones.
The individual incidents in the film are mostly true, but were rearranged as to both the timing and the people involved. (A note at the start of the film acknowledges this.) For instance, of the 76 who escaped, there were indeed 3 who got away and 50 who were murdered in reprisal, but the murders occurred in small groups, not all at once. (14 Germans were executed after the war for their parts in them.)
Roger Bartlett is modeled after Roger Bushell, a British officer who was involved in the real escape and, like Bartlett, was executed for his role therein. The scarring around Richard Attenborough's eyes is a tribute to Bushell, who received such scarring from a competitive skiing accident.