Terry Jones has died at the age of 77, his agent has confirmed.
Born in Wales in February 1942, Jones was an actor, writer, comedian, director and historian best known for his work with the Monty Python comedy troupe.
A statement from Jones's family said: "We are deeply saddened to have to announce the passing of beloved husband and father, Terry Jones.
"Terry passed away on the evening of 21st January 2020 at the age of 77 with his wife Anna Soderstrom by his side after a long, extremely brave but always good humoured battle with a rare form of dementia, FTD.
"Over the past few days his wife, children, extended family and many close friends have been constantly with Terry as he gently slipped away at his home in north London. We have all lost a kind, funny, warm, creative and truly loving man whose uncompromising individuality, relentless intellect and extraordinary humour has given pleasure to countless millions across six decades.
"His work with Monty Python, his books, films, television programmes, poems and other work will live on forever, a fitting legacy to a true polymath.
"We, his wife Anna, children Bill, Sally, Siri and extended family would like to thank Terry's wonderful medical professionals and carers for making the past few years not only bearable but often joyful. We hope that this disease will one day be eradicated entirely. We ask that our privacy be respected at this sensitive time and give thanks that we lived in the presence of an extraordinarily talented, playful and happy man living a truly authentic life, in his words 'Lovingly frosted with glucose'."
Jones and writing partner Michael Palinwrote and performed for several high-profile British comedy programmes, including Do Not Adjust Your Set and The Frost Report, before creating surreal, groundbreaking sketch show Monty Python's Flying Circus with Eric Idle, John Cleese, Graham Chapman, and Terry Gilliam.
He made his directorial debut in 1975 with the team's first big-screen outing, Monty Python and the Holy Grail, which he co-directed with Gilliam, and also directed the subsequent Python films, Life of Brian (1979) and The Meaning of Life (1983).
Beyond Python, Jones co-wrote the TV series Ripping Yarns (1976-79) with Palin, contributed to the screenplay for Labyrinth (1986) and wrote non-fiction books and presented documentaries on medieval and ancient history.
He was diagnosed in 2015 with with primary progressive aphasia, a form of dementia that impairs the ability to speak and communicate.