Born in 1934 in Liverpool, Welland grew up in the Kensington area of Liverpool before moving to Newton-le-Willows, Lancashire, while still a young child. His parents were John Arthur (Jack) and Norah Williams. He attended Newton-le-Willows Grammar School and after National Service he studied at Goldsmiths College and Bretton Hall College of Education, where he gained a teaching diploma and qualified as a Teacher.
As an actor, Welland appeared as PC David Graham in the BBC Television series Z-Cars from 1962 to 1978. He was a sympathetic schoolteacher in a BAFTA-winning performance in the film Kes (1969), and a detective in the Richard Burton film Villain (1971). He appeared as a villain in one 1975 episode of The Sweeney, and was in the series' first cinema spin-off Sweeney! (1977) as Frank Chadwick, a newspaper Editor. His other film appearances include Dennis Potter's Blue Remembered Hills (1979) as the character Willie, and Dancin' thru the Dark (1990). He was also in the television series Cowboys (1980), a comedy about a dodgy builder, with Roy Kinnear.
When Welland had appeared on BBC Radio 4's Desert Island Discs in 1973 he said that most of his own plays "usually champion the individual against the system". He said: "I usually find that it's one man's effort to break through what is usually expected of an individual."
Welland's screenwriting credits include the teleplay about the strike for equal pay Leeds United (1974), the film Yanks (1979), starring Vanessa Redgrave and Richard Gere, which was directed by John Schlesinger, and Twice in a Lifetime (1985), starring Gene Hackman, Ellen Burstyn and Ann-Margret.
Welland won the award for Best Original Screenplay for Chariots of Fire (1981) at the 1982 Academy Awards, and his acceptance speech included the phrase: "The British are coming!" (a quotation from Paul Revere). In the film Chariots of Fire, the sign outside the Church of Scotland in Paris shows the preacher for the 9 am worship to be "C.M. Welland"; he had played a vicar in Straw Dogs (1971). Following Chariots of Fire, he was again commissioned by David Puttnam to write the screenplay for War of the Buttons (1994).
Welland died in London in his sleep on 2 November 2015 at the age of 81. He had Alzheimer's disease for several years prior to his death.
