Terry Jones spent most of the budget on the "Every Sperm Is Sacred" sequence. The rest of the team found out later.
Sensitive to the young actors in the "Every Sperm is Sacred" scene, Sir Michael Palin actually said "those little rubber things on the end of my sock." The word "cock" was dubbed in later.
The kids who sang in the "Every Sperm is Sacred" sketch later said they had no idea what they were singing about.
"The Crimson Permanent Assurance" segment was filmed as if it were a completely separate project. Terry Gilliam got his own soundstage, crew, and cast. This segment continued to expand because, according to Gilliam, nobody told him to stop.
Graham Chapman, who was openly gay, asked to play God in this movie because he was frustrated at the Church of England for refusing to marry him and his partner, David Sherlock. At the time, same-sex marriage was not legal in the United Kingdom, nor recognized by the Church of England.