Keillor told The Associated Press of his firing in an email. In a follow-up statement, he said he was fired over "a story that I think is more interesting and more complicated than the version MPR heard." He didn't give details of the allegation.
"It's some sort of poetic irony to be knocked off the air by a story, having told so many of them myself, but I'm 75 and don't have any interest in arguing about this. And I cannot in conscience bring danger to a great organization I've worked hard for since 1969," Keillor said.
"A person could not hope for more than what I was given," he said.
Minnesota Public Radio confirmed Keillor had been fired, saying it received a single allegation of "inappropriate behavior" and doesn't know of any other similar allegations. MPR said it was notified of the allegation last month and that it stemmed from Keillor's conduct when he was responsible for producing "A Prairie Home Companion."
Keillor retired as host of his long-running public radio variety show in 2016. His hand-picked successor, mandolinist Chris Thile, is in his second season as "Prairie Home" host. After Keillor retired from the show, he continued to work with MPR on other projects.
The firing Wednesday came shortly after Keillor, an avowed Democrat, wrote a syndicated column that ridiculed the idea that Sen. Al Franken should resign over allegations of sexual harassment.
MPR also said the name of the show, produced and distributed nationwide by American Public Media The show has been named "A Prairie Home Companion" for more than 40 years.
In addition, MPR said it will end distribution of "The Writer's Almanac," Keillor's daily reading of a poem and telling of literary events." It also will end rebroadcasts of "The Best of A Prairie Home Companion" hosted by Keillor.
Keillor started "A Prairie Home Companion" as a Saturday evening show in 1974, featuring tales of his fictional Minnesota hometown of Lake Wobegon "where all the women are strong, all the men are good-looking, and all the children are above average."
The show featured musical acts, folksy humor, parody ads for fake products such as Powdermilk Biscuits and the centerpiece, Keillor delivering a seemingly off-the-cuff monologue, "The News From Lake Wobegon," in his rich baritone voice.
Keillor bowed out with a final show at the Hollywood Bowl in July 2016, and turned the show over to Thile, a mandolinist and frequent "Prairie Home" guest musician. Keillor went on a 28-city bus tour this summer, vowing it would be his last tour, but he continues on the road with solo shows.
Keillor still produces the radio show, "The Writer's Almanac," for syndication, and is finishing a Lake Wobegon screenplay and a memoir about growing up in Minnesota.