LOS ANGELES - It was a constant in American television for more than a decade: Viewers could turn on their TVs and find Howard Cunningham in his armchair, reading the newspaper and providing a fatherly voice of reason to young Richie Cunningham and his friends on "Happy Days."

Tom Bosley made the role famous during the long-running sitcom, earning a place as one of the most memorable fathers in TV history.

Bosley died Tuesday at the age of 83 after suffering heart failure at a hospital near his Palm Springs home. Bosley's agent, Sheryl Abrams, said he was also battling lung cancer.

His death brought fond remembrances of the nostalgic ABC show, which ran from 1974 to 1984. On Saturday, TV viewers lost another surrogate parent, Barbara Billingsley, who portrayed June Cleaver in "Leave It To Beaver."

Both shows showcased life in the 1950s - before Vietnam, Watergate and other tumultuous events of the '60s and '70s - when life was simpler.

"Kids were watching their parents grow up, and parents were watching themselves grow up. And that was the key to success of that show," Bosley said in a 2000 interview.

Bosley initially turned down the offer for a costarring role in "Happy Days."

"After rereading the pilot script," he recalled in a 1986 interview, "I changed my mind because of a scene between Howard Cunningham and Richie. The father/son situation was written so movingly, I fell in love with the project."

Viewers did too.

"Happy Days," which debuted in 1974, slowly built to hit status, becoming television's top-rated series by its third season.

TV Guide ranked Bosley's Howard Cunningham character at No. 9 on its list of the "50 Greatest TV Dads of All Time" in 2004. The distinction puts "Mr. C," as his character was affectionately known on the show, right alongside Ward Cleaver, Andy Taylor, Dr. Huxtable and Mike Brady as some of the best-ever TV dads.

"Tom's insight, talent, strength of character and comic timing made him a vital central figure in the 'Happy Days' experience. A great father and husband, and a wonderful artist, Tom led by example, and made us all laugh while he was doing it," said a statement from Ron Howard, who played Richie Cunningham.

"My last conversations with Tom reflected the love of life and peace of mind that he always maintained throughout his full and rewarding life. I miss him already," Howard said.

"He was my husband for 11 years and the father of the company in many ways," said Marion Ross, who played Marion Cunningham on the show. "He was so smart he could fix the end of a joke or a scene on the spot. We made a perfect couple. I played piccolo to his tuba."

Angela Lansbury played Bosley's unfaithful wife in the 1964 Peter Sellers film "The World of Henry Orient." Then, from 1984 to 1988, Bosley played a recurring role in Lansbury's long-running TV series, "Murder, She Wrote," as folksy Sheriff Amos Tupper.

"He was a wonderfully interesting actor, and very much a part of the early success of 'Murder, She Wrote.' Working with him in the early days of the show gave me tremendous confidence," Lansbury said.

Bosley also played the crime-solving priest in television's "The Father Dowling Mysteries," which ran from 1989 to 1991.

"Happy Days" led to other television spinoffs such as "Laverne and Shirley" and "Joni Loves Chachi." The show also made a star of Henry Winkler, who played hip-talking, motorcycle-riding hoodlum Arthur "Fonzi" Fonzarelli.

"Tom was a family member, both on and off the sound stage. We acted together, traveled together and played charades together," Winkler said in a statement.

"He was a loving husband, a doting father and a fantastic grandfather. He will be so missed but never forgotten by the Winkler Family or the world."

Although "Happy Days" brought him his widest fame, Bosley had made his mark on Broadway 15 years before when he turned in a Tony Award-winning performance in the title role in "Fiorello!"

His Broadway triumph depicted the life of New York's colorful reformist mayor of the 1930s and '40s, Fiorello La Guardia. For two years, Bosley stopped the show every night when he sang in several languages, depicting La Guardia during the years the future mayor worked at New York's Ellis Island, aiding arriving immigrants.

The play won a Pulitzer Prize and Bosley received the Tony for best actor in a musical.

After failing to duplicate his success in "Fiorello!," Bosley moved to Hollywood in 1968. He would not return to Broadway until 1994 when he originated the role of Belle's father in Disney's production of "Beauty and the Beast."

In Hollywood, the rotund character actor found steady work appearing in the occasional movie and as a regular on weekly TV shows starring Debbie Reynolds, Dean Martin, Sandy Duncan and others.

During the 1990s, Bosley toured in "Beauty and the Beast" and "Show Boat," playing Captain Andy in the latter.

Bosley made only a handful of theatrical movies. Among them: "Love With the Proper Stranger," ''Divorce American Style," ''The Secret War of Henry Frigg," ''Yours, Mine and Ours."

Bosley capitalized on his fame from "Happy Days" to serve as a pitchman for GLAD trash bags along with other products.

Born in Chicago in 1927, Bosley served in the Navy before returning to his hometown to study at DePaul University. Intrigued with acting, he enrolled at the Radio Institute of Chicago and began appearing in radio dramas.

Bosley married dancer Jean Eliot in 1962 and the couple had one child, Amy. Two years after his wife's death in 1978, Bosley married actress-producer Patricia Carr, who had three daughters from a previous marriage.

Associated Press writers Robert Jablon in Los Angeles and Frazier Moore in New York contributed to this story.