Joseph Fiennes lost 20 pounds for the role of Major Gibson by keeping a strict diet and exercise regime during the five months of shooting.
In late 2004, many months before this film was released to the public in August 2005, US Ambassador to the Philippines Frank Ricciardone contacted Miramax producers Harvey and Bob Weinstein, with whom he was acquainted, to request a personal favor. Ambassador Ricciardone asked if the Weinsteins would consent to allow the U.S. Embassy in Manila to hold special screenings of this film during the Embassy's celebration of the 60th anniversary of the Cabanatuan raid. Remarkably, the Weinsteins gave their blessing for the U.S. Embassy to make limited use of the film, an act that had no precedent. Thus, during February 2005, seven months before its public release, the film was screened for a limited audience of both American and Filipino employees of the U.S. Embassy, plus some family members, as well as a select group of people involved in the movie's production (Director John Dahl was present), the Hampton Sides novel that provided some of the film's material (Mr. Sides was present), and the 60th anniversary ceremonies at Cabanatuan. The film was screened at a theater in the Greenbelt 3 Mall at Ayala Center in Makati - the main financial and entertainment district of Manila.
Almost none of the U.S. Army soldiers seen in the film wear the distinctive and famous M1 helmet; the main force depicted onscreen are the 6th Ranger Battalion, who left their helmets behind and wore soft 'Swing caps' for the raid. The reason for this was that the helmets were bulky, heavy, and noisy if struck. They were also known to give a glare, which would give their positions away on such a secretive mission.
Although he was not among the real-life officers portrayed in the movie, Colonel Arthur "Bull" Simons was a young Army Ranger Captain who took part in the raid on Cabanatuan and was awarded the Silver Star for his actions during the raid. During the height of the Vietnam War, Colonel Simons led the famous raid on Son Tay in an attempt to rescue POWs.