Chicago’s popular comedy theaters Second City and iO both trace their roots to David Shepherd, an innovative theater producer and actor who died this week at age 94 in Pioneer Valley, Massachusetts.

His death was announced on Facebook by Shepherd’s longtime friend Michael Golding, who wrote, “He was in no pain and his transition was peaceful.”

A New York native, Shepherd already had studied at Harvard and Columbia when he arrived in Chicago in 1952 and took up with the dramatically inclined students of University Theatre at the University of Chicago. Off campus, he was among the founders of Playwrights Theatre Club, which presented plays at various North Side locations.

After that collapsed, Shepherd and Paul Sills launched the Compass Players in 1955 with a Chicago troupe that at times included future stars Barbara Harris, Shelley Berman, Mike Nichols and Elaine May.

Shepherd performed in and produced shows there that included improvised scenes based on the day’s news. He relocated the company to St. Louis in 1957. As he kept the Compass concept alive in various other places, some of his Chicago associates opened a coffeehouse called The Second City and put on shows there using improvisational ideas similar to Shepherd’s.

“Simply put, there would be no Second City without David Shepherd,” the theater said in a statement Tuesday.

While he held no formal role there, Shepherd occasionally sat in as a director.

“David was a passionate scholar and champion of the work,” Second City CEO Andrew Alexander said in the statement. “His mind was always in innovation mode, and he was never lacking for fresh new ways to explore the world of improvisation.”

In the ensuing years, Shepherd continued experimenting with new improv forms, and in the 1970s he and Howard Jerome devised Improv Olympics in New York.

“There were 10 events, and each one highlighted a different dramatic skill,” he told the Sun-Times in 2005. “They had to do with character, emotion, pantomime and also basic skills like telling a story, singing a song, working with no words at all.”

He brought the improv competition to Chicago in partnership with aspiring actor and director Charna Halpern. As their visions of the format started to diverge, Shepherd returned to New York and left Halpern to reshape ImprovOlympic (now iO) as a showcase for the ideas of Second City veteran Del Close.

“If I had been able to produce that kind of comedy theater I would have been doing it up to this day,” said Shepherd, who did not believe in limiting improv to just comedy. “But I just was not able to do it. I didn’t have my mind in it.”