His son, John Christopher, said the actor died from non-small cell lung cancer at his home in Pasadena.
He was 84.
The actor played the role of Father John Mulcahy on "M*A*S*H" from 1972 to 1983 and in the follow-up series "After M*A*S*H*" from 1983 to 1985.
He also had parts in the movies "The Fortune Cookie" and "With Six You Get Eggroll," and the TV shows "Hogan's Heroes" and "Gomer Pyle, U.S.M.C."
His agent, Robert Malcom, told the Associated Press that William Christopher was diagnosed with cancer more than a year ago and had been in hospice since the beginning of the week.
"M*A*S*H" co-star Loretta Swit released the following statement to Eyewitness News:
"Our dear Bill and his goodness are a great argument for there being a heaven. I never heard him complain or lose his temper. Everyone adored him. A great sense of humor and a great humanitarian. He became TV's quintessential padre as Father Mulcahy on 'M*A*S*H.' It was the most perfect casting ever known. He was probably responsible for more people coming back to the church. If God is nigh, then surely he or she will welcome Bill with open arms."
IN MEMORIAM: Celebrities and notable figures who have recently passed away
William Christopher leaves behind his wife Barbara and his sons John and Ned.
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