Hard Stats:

Producer: Python Pictures
Directors: Terry Gilliam & Terry Jones
Screenwriters: Graham Chapman, John Cleese, Eric Idle, Terry Gilliam, Terry Jones, Michael Palin

Cast:

Graham Chapman - King Arthur
John Cleese - Sir Lancelot, The Black Knight, Tim the Enchanter
Eric Idle - Sir Robin, Brother Maynard
Terry Gilliam - Sir Bors, Old Man from Scene 24
Terry Jones - Sir Bedevere, Prince Herbert
Michael Palin - Sir Galahad, King of Swamp Castle, Leader of the Knights who say Ni!

Trivia:

Most of the castle shots were filmed on location at Doune Castle and Stalker Castle. These were the interior shots, and rooms were frequently reused with different furnishings. Castles shot from the distance were either these two castles from different angles, or plywood models.

Graham Chapman was a hardcore alchoholic at the time of filming, and frequently imbibed between takes of Flying Circus to calm his nerves. Since the locations the Holy Grail were being filmed at were so remote, Graham was unable to procure any alchohol, and suffered from delerium tremens as a result. A double had to be used during the bridge crossing scene.

Future writer Iain Banks was among the extras used in the film.

The tiny budget of £150,000 was donated by popular music acts Pink Floyd, Jethro Tull, and Led Zeppelin. Pink Floyd donated the most, having raised the funds during their tour in support of "Dark Side Of The Moon", and they were such fans that they would break from recording sessions to watch "Monty Python's Flying Circus".

King Arthur is the only one who wears actual chainmail in the film. The rest of the knights all wear painted wool. British weather being what it is, most of the actors were damp and clammy by the end of the day. To make matters worse, the remoteness of the shooting locations often meant that local hotels had inadequate accomodations.

In actual medeival cathedrals, the stained glass windows were frequently decorated with graphic depictions of the virtues and vices. The vice of cowardice was commonly depicted as a knight running away from a rabbit. This is what inspired the scene with the killer rabbit in the film.

The gag in which the knights are followed by pages banging coconuts together was not an original concept. It was written into the script only when the Pythons realized the film's budget would not include horses.

The film had been portrayed live as a theater adaptation before, but in 2006 an official Broadway musical was created called "Spamalot".