In his personal life, Chapman was openly homosexual and a strong supporter of gay rights, and was in a long-term partnership with David Sherlock. He was an alcoholic during his time at Cambridge and the Python years, and quit drinking shortly before working on "Life of Brian". He later became an enthusiast and patron of the Dangerous Sports Club. Chapman died of tonsil cancer which spread to his spine in 1989, on the Pythons' 20th anniversary. His life and legacy were commemorated at a private memorial service at St Bartholomew's with the other five Pythons.