Phil Donahue, talk show host pioneer and husband of Marlo ...

Phil Donahue, an innovative TV host who rose to fame in the late 1960s after being the first person to interact with a studio audience and bring new ideas into American living rooms,died Sunday, his family said.

He was 88.

The cause of his death was not immediately disclosed, though his family said he'd been suffering from a "long illness."

"Groundbreaking TV talk show journalist Phil Donahue died Sunday night at home surrounded by his wife of 44 years Marlo Thomas, his sister, his children, grandchildren and his beloved golden retriever Charlie," said a statement from his family.

"Donahue was 88 years old and passed away peacefully following a long illness."

At his peak, his nationally syndicated "The Phil Donahue Show" — later renamed "Donahue" — was a ratings hit and precursor to similar shows by hosts Montel Williams and Jerry Springer.

Oprah Winfrey described Donahue as a trailblazer who invented smart talk in the afternoon and brought startling new ideas into the living rooms and laundry rooms of American women.

“His show debuted nationally, and the whole country came to know his personal brand of issue-driven straight talk,” Winfrey said in 2002.

“If there had been no Phil Donahue show, there would be no 'Oprah Winfrey' show. He was the first to acknowledge that women are interested in more than mascara tips and cake recipes — that we’re intelligent, we’re concerned about the world around us, and we want the best possible lives for ourselves.”

But Donahue ushering in a new wave of television happened by accident.

He first tried the audience participation format while taping his show in Dayton, Ohio, in 1967. The audience arrived for a variety show which, unbeknownst to them, had been canceled, according to The New York Times.

Donahue suggested letting them watch his interview with Madalyn Murray O’Hair, then a celebrity for being an atheist. Soon, he allowed members of the audience to ask questions. Decades later, his brand of television became an industry standard that continues today.

“Phil Donahue essentially started this company and began an entire industry in daytime syndication,” Bob Turner, then president of Multimedia Entertainment, said in a statement to the Times in 1996 when Donahue announced his retirement.

Donahue was a contributor to NBC's "TODAY" show from 1979 until 1988. He returned to television in 2002 as a prime-time host on MSNBC but his show was canceled after less than a year. (MSNBC and NBC News share the same parent company, NBCUniversal.)

Away from interviewing entertainers and touching on polarizing topics such as war and abortion, Donahue was a self-described feminist.

He became an advocate for women’s rights after noticing how women decades ago were treated in the workplace.

“I was always proud of that,” Donahue said, during a taping of NBC’s "Megyn Kelly Today" in 2017.

In the 1960s, “a boss could tell his secretary to walk around the room so he could look at her; poke her in the chest and get away with it. There was nothing she could do about it,” Donahue said during the episode.

He also noted how many women at the time didn’t host daytime talk shows unlike now.

“It reminds me of how far we’ve come, how far women have come,” he said.

Donahue was inducted into the Television Academy Hall of Fame in 1993.

During that ceremony, Thomas recalled how her husband put the toughest issues faced by Americans in stark and understandable language.

"He forced us to take a hard look at the real and imagined goals of the Persian Gulf War, the pros and cons of condom distribution in schools and legalized drug abuse," she said.

"He laid out the savings and loan crisis in terms so plain that anybody who had ever taken freshman math could get a grip on the ripoff."

Earlier this year, President Joe Biden honored him with a Presidential Medal of Freedom, the nation's highest civilian honor.

The White House called him a "television pioneer," whose daytime chat show became "one of the most influential" programs of its time.

In lieu of flowers, loved ones asked for donations to be made to the St. Jude Children’s Research Hospital or the Phil Donahue/Notre Dame Scholarship Fund.

Donahue's wife and father-in-law, Danny Thomas, have long been associated with the St. Jude Children’s Research Hospital.

Donahue married Thomas in 1980, making them one of the most enduring couples in show business.

She's best known for her work on the groundbreaking sitcom "That Girl" which ran for five seasons on ABC between 1966 and 1971.

It was one of the first network shows to focus on a single woman seeking a career. More shows with that nature would follow in the 1970s and 80s, such as "The Mary Tyler Moore Show" and "Kate and Allie."