Werner Klemperer, Howard Caine, Leon Askin, and John Banner, who portrayed the chief Germans Klink, Hochstetter, Burkhalter, and Schultz, were all Jewish. All of them also served in the U.S. Armed Forces during World War II. Klemperer was born in Cologne, Germany and Banner and Askin were both born in Vienna, Austria, and the three of them immigrated to the United States after fleeing the Nazi regime.

Werner Klemperer only agreed to play Colonel Klink once he was assured (by the show's creator) that Klink would never succeed in his schemes.

Robert Clary was a survivor of the Holocaust. Werner Klemperer escaped Nazi Germany in 1933.

The leather jacket that Bob Crane wore on this show, was originally worn by Frank Sinatra in Von Ryan's Express (1965). It was later worn by Greg Kinnear in Koukussa (2002).

Early in production planning, it was decided to make it always be winter, with snow on the ground, and frost on the windows. This was to prevent problems with continuity, and to allow the episodes to be shown in any order. Since much of the filming was done in the summer, the cast members had to wear coats and act cold, even when the temperature was over ninety degrees Fahrenheit (thirty-two degrees Celsius).

Larry Hovis (Sergeant Andrew Carter) refused to remove his wedding ring for the series. He wore gloves for the majority of his performance (although there were occasions when the ring was visible).

In the pilot episode, Carter was a Lieutenant, and was only going to appear in that one episode.

The show was still very popular in its final season on the air. However, it was caught up in the "rural purge" that took place just before the 1971-1972 television season. The main reason it was canceled, was due to the fact that it was felt that the show mainly appealed to rural audiences and older people in much the same way that shows like The Beverly Hillbillies (1962), Green Acres (1965), and Hee Haw (1969) were.

The character of Sergeant Schultz, prior to the war, had been the President of a successful toy manufacturing company. Colonel Klink tried to become a bookkeeper at the toy company after the war.

Richard Dawson stated that when he got the part of Newkirk, Mike Dann (then President of CBS) asked him to use a Cockney accent, rather than his native Liverpool accent. Dann believed that the Cockney accent would sound more familiar to American viewers. Shortly after this decision was made, "Beatle-mania" swept the nation. The Beatles were also from Liverpool, and spoke with thick Liverpool accents, making Americans more accustomed to the sound of it. Dawson claimed he brought this to the attention of Dann, lightheartedly mocking him for the decision.

The car seen leaving the camp in the opening credits and from time to time during the series, is a Mercedes model G4 Parade Car. The six-wheeled, three-axle vehicle had four wheel drive on the rear wheels (6 x 4) and was popular amongst the German Military elite.

Most night scenes were filmed using a "day for night" filter, which is a special attachment used to make scenes filmed during the day, to look like night.

The show was famous for recycling actors and actresses in different roles. For example: William Christopher (best known as Father Mulcahy on M*A*S*H (1972)) played a POW, a German soldier, and a British pilot. Harold J. Stone played an American Agent and a German General. Antoinette Bower played Berlin Betty, a German scientist, and an underground Agent. Arlene Martel appeared as resistance fighter "Tiger" in several episodes, and also as Olga and Gretchen in other episodes.

Even though Klink acts like a coward, his military decorations indicate he is a combat hero from World War I and World War II.

The Stalag 13 outdoor set was located at the northwest corner of the Forty Acres backlot in Culver City, California, near Lucerne Avenue and Higuera Street, southeast corner. Early in the series' 1968 hiatus, the set was used in Vaarallinen tehtävä: Trial by Fury (1968), where it doubled as a South American prison. After the series cancellation, it was used as Medical Camp 9 in the Nazi sex thriller Ilsa - SS:n naarassusi (1975), during the filming of which it was burned. The cleared area became the site of a new set for Akka jota ei saatu hengiltä (1975). The backlot was then bulldozed in 1976, and is now an industrial park. The location was previously used for the Tara plantation façade in Gone with the Wind (1939).

Ivan Dixon (Kinch) left the series at the end of the fifth season (the only regular cast member to do so), stating that he was fed up with the posturings of Bob Crane, Werner Klemperer, and Richard Dawson. He was replaced by Kenneth Washington for the final twenty-four episodes. Also, there was no mention of what happened to Kinch following Dixon's departure.

The various secret code names that Colonel Hogan and his outfit used, were fairy tale names of "Papa Bear", "Goldilocks", and "Little Red Riding Hood". Colonel Hogan's codename was "Goldilocks" in the series debut, contacting an underwater submarine in Hogan's Heroes: The Informer (1965).

The nearest town to Stalag 13 was Hammelburg.

Cynthia Lynn, who played Klink's secretary "Helga" in the first season, was replaced by Sigrid Valdis, who played "Hilda" at the insistence of Bob Crane after Valdis began dating (and later married) Bob Crane.

The black and white pilot episode originally included a Russian character, who was played by Leonid Kinskey. Kinksey refused to continue with the series, because he became uncomfortable with having Nazi characters starring in a comedy.

In the German dubbed version, very often the salute "Heil Hitler" was changed to "Heil Kräuter!" (literally translated: medicinal herb). Also, when the show alluded to bombing and killing, the dialogue was often modified as well. For instance, when the Americans destroyed a munitions factory, the German version made it a toilet paper factory, and when Sergeant Schulz reported the Allies having bombed Hamburg, it was revised to the Royal Air Force dropping candy as a "propaganda maneuver".

Another recurring character was Burkhalter's sister Frau Gertrude Linkmeyer, usually played by Kathleen Freeman, but on one occasion, in the fourth year, by Alice Ghostley, who also appeared in a final season episode as the wife of a Nazi Field Marshal.

The series was originally supposed to take place in a regular American prison. But Creators Bernard Fein and Albert S. Ruddy re-wrote the teleplay when they heard that NBC was developing the pilot Campo 44 (1967), which took place in an Italian POW camp.

John Banner (Sergeant Schultz) once turned up to the set drunk, and fell into razor wire, causing multiple lacerations. Banner missed multiple episodes in season three, due to the injury.

As of 1 April 2018, only two of the original main cast are still alive. They are Robert Clary (Corporal LeBeau) and Kenneth Washington (Sergeant Baker).

Warner Klemperer's father had a famous rock and roll connection. Otto Klemperer conducted the classical music heard in the Beatles movie, Help! (1965).

The ornate helmet that sat on the desk of Colonel Klink, Werner Klemperer was a pre-World War Prussian army Pickelhaube (Spiked Helmet), possibly a family heirloom, as it is clearly one of his most prized possessions. As the helmet used in the show differs in several respects from museum examples, it is probably a replica produced by the Props Department, and not a real antique.

For the first several seasons the "snow" on the roofs and on the ground was actually salt. By the fourth season, much of the snow on the roofs had been replaced by patches of white paint. By the sixth season, all the patches of snow on the roofs and many of the patches of snow on the ground, especially in the high traffic areas, were also just paint.

Kinchloe and Newkirk did all of the fake German orders, and provided most of the disguised German voices used on the telephone.

General Burkhalter's Iron Cross is the "Knight's Cross with diamonds and swords".

Characters travelling outside of Germany: Hogan and Klink travelled to London, England. Hogan, Klink, LeBeau, Kinchloe and Schultz travelled to Paris, France.

Werner Klemperer was the son of famed orchestral conductor Otto Klemperer.

Colonel Klink and Sergeant Schultz nicknamed Corporal LeBeau "Cockroach", for his small height.

Werner Klemperer (Colonel Klink) once said that during production, his father told him, "Your acting is fine on the show, but who writes this stuff?"

Bob Crane (Colonel Robert Hogan) and Werner Klemperer (Colonel Wilhelm Klink) are the only actors to appear in all 168 episodes.

Carter was from North Dakota, and Kinch was from Detroit, Michigan.

A musician, especially a percussionist, from a young age, Bob Crane provided the drums for the show's theme song. His skills on the skins were featured early in the program, in season one, episode five, "The Flight of the Valkyrie", and in season six, episode twenty-three, "Look at the Pretty Snowflakes", where he performed the drum solo during "Cherokee".

Howard Caine appeared in two early episodes playing different characters before he took on the role of Major Hochstetter. They were season one, episode seventeen, "Happy Birthday, Adolf", as Major Keitel, and season two, episode five, "The Battle of Stalag 13", as Colonel Feldkamp.

German film distributor KirchGruppe acquired the rights to this show, but did not broadcast it for many years, due to fears that it would offend viewers. It was first broadcast on German television in 1992, but the program failed to connect with viewers. However, after the dialogue was re-written to make the characters look even more foolish (which ensured that the viewers understood the characters were caricatures), the show became successful.

Schultz's rank is Master Sergeant.

John Banner appeared in a role similar to his Sergeant Schultz role, in 36 tuntia (1964).

The sign outside Barracks 2 translates to English as : "Forbidden: 1. Strict orders have been given to the German troops around Brussels to shoot any civilian cyclist. 2. People who, after the fifteenth of December, are still in possession of carrier pigeons, as well as other persons who, by signals or any other means, cause annoyance to German military interests, will be judged by court martial." It is dated December 13, 1944, and signed by General H. Heinrichs (who shares the same initials as the show's Art Director Howard Hollander).

John Banner died on his sixty-third birthday in Vienna, Austria, which was also his birthplace.

In the original black and white pilot, General Burkhalter was a Colonel.

Married cast: Schultz is married with five children, but this doesn't stop him from dating other women. LeBeau may or may not have been married.

Despite some coincidental similarities (both have a "Sergeant Schultz" character, and a somewhat put-upon Commandant), this show was not inspired by the movie, Vankileiri 17 (1953), as some may think.

Among the recurring characters who appeared on the show were female French resistance fighter Tiger (Arlene Martel), Marya the White Russian (Nita Talbot), and the bumbling R.A.F. officer, Colonel Crittendon (Bernard Fox).

For the first five seasons, Sergeant Carter wore a distinctive leather flight jacket. The right sleeve and part of the front was white. This jacket was replaced in the sixth season with one that was all brown.

Ivan Dixon's character's name was Sergeant James Kinchloe. There was a test pilot who was killed, named "Iven Kincheloe".

Schultz always called Hogan and his men "jolly jokers" whenever they played a trick on him.

Werner Klemperer and John Banner appeared together on Alfred Hitchcock Presents (1955) season one, episode twenty-one, "Safe Conduct".

The standard rifle of the German Army in World War II, was the Mauser K98, but the rifle carried by Sergeant Hans Schultz (John Banner), and most of the other German guards at Luft Stalag 13, was a U.S. Military issue Krag Jorgensen rifle. The Krag Jorgensen, used by the U.S. Military in the early 1900s, was most likely substituted for the Mauser, due to its general resemblance to the Mauser rifle, and the fact that the studio had them on-hand. They were getting hard to come by in the 1960s.

Lasted on the air for six years, although American involvement in World War II lasted less than four years.

General Burkhalter's staff car was an American hybrid, with a Mercedes-Benz logo on it. Colonel Klink's staff car was a 1936 Mercedes 260D, although in some episodes, it was the Pullman limousine model, while in others, it was the standard model.

Whenever Colonel Hogan wanted to butter up Colonel Klink, he would refer to him as "The Iron Colonel" or "The Iron Eagle".

Cast who were never seen in women's clothing were the two African-American actors: Kenneth Washington, in the role of Sergeant Richard Baker, (season six), and Ivan Dixon, as Sergeant James Kinchloe (seasons one through five), in addition to Werner Klemperer, as Colonel Wilhelm Klink (the entire series).

Werner Klemperer and John Banner appeared in Operation Eichmann (1961).

Interestingly, when the show was being cast, Werner Klemperer auditioned for the role of Sergeant Schultz, and John Banner was considered for the role of Commandant Klink. However, after the auditions, it was decided to switch them to their famous roles.

There was a POW camp near Hammelburg, Germany. Stalag 13-C was a German Army World War II prisoner-of-war camp (Stammlager) built on what had been a training camp at Hammelburg, Lower Franconia, Bavaria, Germany.

Some of the vehicles had the steering wheel on the left hand side of the vehicle, and the others had the steering wheel on the right hand side. The steering wheel should be on the left hand side of all of the vehicles, because they drive on the right hand side of the road in Germany.

Co-Creator Albert S. Ruddy refused to be directly involved with the series after the pilot, because he did not want to be contracted to work on a television series.

Newkirk and Le Beau made most of the German uniforms that were worn by Hogan's men.

Among the six seasons, as they originally televised, seasons one, two, and five were on Friday evenings. Seasons three and four were on Saturday evenings, and season six's were on Sunday evenings.

Two cast members, who were never called by only their last names, were African-American actors: Kenneth Washington as Sergeant Richard Baker (season six). and Ivan Dixon as Sergeant James "Kinch" Kinchloe (seasons one through five).

Colonel Hogan's fake name to test new POW's that may be possible double Agents for Nazis and report Hogan's secret group of heroes, was "Major Campbell". The name was mentioned twice in the series' debut, on Friday, September 17, 1965.

In the series, Hogan states he is from Bridgeport, Connecticut, but on other occasions, German "intelligence" officers state that he was born and raised in Ohio.

Harold Gould (General Von Schlomm) was Jewish in real-life, and also served in the U.S. Armed Forces during World War II.

Besides being in contact with London, Hogan had radio communications with a submarine, which was used to assist prisoners in escaping.

Throughout the series, Colonel Hogan and Sergeant Carter are said to be from the U.S. Air Force. This is incorrect. There are times they are said to be Army Air Corps. This is also incorrect. The U.S. Air Force did not exist until 1947. Prior to that, this branch was part of the Army. It was the U.S. Army Air Corps from 1926 until June of 1941 (before the U.S. entered World War II). From June 1941, until the U.S. Air Force was created separately from the Army in 1947, it was the U.S. Army Air Forces. Actually, the Army Air Corps became a combat branch of the U.S. Army Air Force, and was not done away with completely until 1947, when the U.S. Air Force was created.

Howard Caine and Werner Klemperer appeared in Judgement at Nuremberg (1961).

The familiar drum cadence heard throughout the show is virtually identical to the drum cadence played whenever the Nazis were shown, in The Longest Day (1962).

In S4-E26, Schultz suggests a German Chocolate Cake for Hogan's birthday. However, the dessert was not invented until 1957. Also, it's not from the country of Germany, but was named after Sam German who worked for Baker's Chocolate Company in America in 1852.

The real-life Stalag XIII-C was a prisoner-of-war camp located in Hammelburg, Bavaria, the same area as the fictional Luft-Stalag 13 of the series, but other than the name and location, the two bore no resemblance to each other. Stalag XIII-C, and the nearby Oflag XIII-B (primarily used to house higher ranking officers), were overcrowded, lacking in basic amenities such as heat or running water, and the prisoners were kept in generally squalid conditions. The campuses were liberated by Combat Command B of the U.S. 14th Armored Division on April 6, 1945. Germany subsequently surrendered unconditionally to the Allies on May 8, 1945.

Interestingly, Robert Hogan was considered for the role of Colonel Hogan. If he had gotten the role, it would have been one of the few times where an actor played a character with the same name as his.

In Australia, it was the screening network's only series in the Top 30 series and programs.

Richard Dawson was originally offered the role of Hogan but turned it down, believing his accent would make it unbelievable for American audiences.

In the fourth season, episode titled "Will the real Colonel Klink please stand up against the wall?" the opening scene shows General Burkhalter pointing to various places on a map talking about sabotage around those areas, however the map appears to be a map of London. Later, the same map is again seen on a table with Colonel Hogan and his men talking about a sabotage mission.

Bing Crosby Productions originally presented the idea to NBC, but its executives found the pilot episode so funny, they didn't think any later episode could top it, so they passed and CBS picked it up.