Kirk Douglas, the intense, muscular actor with the dimpled chin who starred in Spartacus, Lust for Life and dozens of other films, helped fatally weaken the blacklist against suspected Communists and reigned for decades as a Hollywood maverick and patriarch, died Wednesday, his family said. He was 103.

"To the world, he was a legend, an actor from the golden age of movies who lived well into his golden years, a humanitarian whose commitment to justice and the causes he believed in set a standard for all of us to aspire to," his son Michael said in a statement on his Instagram account.

Kirk Douglas' death was first reported by People magazine.

His granite-like strength and underlying vulnerability made the son of illiterate Russian immigrants one of the top stars of the 20th century. He appeared in more than 80 films, in roles ranging from Doc Holliday in Gunfight at the O.K. Corral to Vincent van Gogh in Lust for Life.

He worked with some of Hollywood's greatest directors, from Vincente Minnelli and Billy Wilder to Stanley Kubrick and Elia Kazan. His career began at the peak of the studios' power, more than 70 years ago, and ended in a more diverse, decentralized era that he helped bring about.

Always competitive, including with his own family, Douglas never received an Academy Award for an individual film, despite being nominated three times — for Champion, "The Bad and the Beautiful and Lust for Life.

But in 1996, the Academy of Motion Picture Arts and Sciences awarded him an honorary Oscar. His other awards included a Presidential Medal of Freedom and a lifetime achievement award from the American Film Institute.

He was a category unto himself, a force for change and symbol of endurance.

In his latter years, he was a final link to a so-called Golden Age, a man nearly as old as the industry itself.

In his youth, he represented a new kind of performer, more independent and adventurous than Clark Gable, Spencer Tracy and other giants of the studio era of the 1930s and 1940s, and more willing to speak his mind.

• Hollywood acting legend Kirk Douglas dies aged 103

Reaching stardom after World War II, he was as likely to play cads (the movie producer in Bad and the Beautiful, the journalist in Ace in the Hole) as he was suited to play heroes, as alert to the business as he was at home before the camera. He started his own production company in 1955, when many actors still depended on the studios, and directed some of his later films.

A born fighter, Douglas was especially proud of his role in the the downfall of Hollywood's blacklist, which halted and ruined the careers of writers suspected of pro-Communist activity or sympathies. By the end of the '50s, the use of banned writers was widely known within the industry, but not to the general public.

Douglas, who years earlier had reluctantly signed a loyalty oath to get the starring role in Lust for Life, provided a crucial blow when he openly credited the former Communist and Oscar winner Dalton Trumbo for script work on Spartacus, the epic about a slave rebellion during ancient Rome that was released in 1960. (A few months earlier, Otto Preminger had announced Trumbo's name would appear on the credits for Exodus, but Spartacus came out first.)

"Everybody advised me not to do it because you won't be able to work in this town again and all of that. But I was young enough to say to hell with it," Douglas said about Spartacus in a 2011 interview with The Associated Press. "I think if I was much older, I would have been too conservative: 'Why should I stick my neck out?'"

Douglas rarely played lightly. He was compulsive about preparing for roles and a supreme sufferer on camera, whether stabbed with scissors in Ace in the Hole or crucified in Spartacus.

Critic David Thomson dubbed Douglas "the manic-depressive among Hollywood stars, one minute bearing down on plot, dialogue and actresses with the gleeful appetite of a man just freed from Siberia, at other times writhing not just in agony but mutilation and a convincingly horrible death."

Douglas' personal favorite was the 1962 Western Lonely are the Brave, which included a line of dialogue from a Trumbo script he called the most personal he ever spoke on screen: I'm a loner clear down deep to my very guts.

The most famous words in a Douglas movie were spoken about him, but not by him.

In Spartacus, Roman officials tell a gathering of slaves their lives will be spared if they identify their leader, Spartacus. As Douglas rises to give himself up, a growing chorus of slaves jump up and shout, "I'm Spartacus!"

Douglas stands silently, a tear rolling down his face.

As Michael Douglas once observed, few acts were so hard to follow. Kirk Douglas was an acrobat, a juggler, a self-taught man who learned French in his 30s and German in his 40s.

Life was just so many walls to crash through, like the stroke in his 70s that threatened — but only threatened — to end his career. He continued to act and write for years and was past 100 when he and his wife published Kirk and Anne: Letters of Love, Laughter, and a Lifetime in Hollywood.

He was born Issur Danielovitch to an impoverished Jewish family in Amsterdam, N.Y.. His name evolved over time. He called himself Isidore Demsky until he graduated from St. Lawrence University.

He took the name Kirk Douglas as he worked his way through the American Academy of Dramatic Arts, choosing "Douglas" because he wanted his last name still to begin with "D" and "Kirk" because he liked the hard, jagged sound of the "K."

Douglas was a performer as early as kindergarten, when he recited a poem about the red robin of spring. He was a star in high school and in college he wrestled and built the physique that was showcased in many of his movies. He was determined, hitchhiking to St. Lawrence as a teen and convincing the dean to approve a student loan. And he was tough. One of his strongest childhood memories was of flinging a spoonful of hot tea into the face of his intimidating father.

"I have never done anything as brave in any movie," he later wrote.

Beginning in 1941, Douglas won a series of small roles on Broadway, served briefly in the Navy and received a key Hollywood break when an old friend from New York, Lauren Bacall, recommended he play opposite Barbara Stanwyck in The Strange Love of Martha Ivers.

He gained further attention with the classic 1947 film noir Out of the Past and the Oscar-winning A Letter to Three Wives.

His real breakthrough came as an unscrupulous boxer in 1949′s "Champion," a low-budget production he was advised to turn down.

"Before 'Champion' in 1949, I'd played an intellectual school teacher, a weak school teacher and an alcoholic," Douglas once said in an interview with the AP. "After 'Champion,' I was a tough guy. I did things like playing van Gogh, but the image lingers."

He had long desired creative control and "Champion" was followed by a run of hits that gave him the clout to form Bryna Productions in 1955, and a second company later.

Many of his movies, such as Kubrick's Paths of Glory, The Vikings, Spartacus, Lonely Are the Brave and Seven Days in May, were produced by his companies.

His movie career faded during the 1960s and Douglas turned to other media.

In the 1970s and 1980s, he did several notable television films, including "Victory at Entebbe" and "Amos," which dealt with abuse of the elderly.

In his 70s, he became an author, his books including the memoir The Ragman's Son, the novels Dance With the Devil and The Gift and a brief work on the making of Spartacus.

"We are living in a town of make-believe," he told The Associated Press in 2014. "I have done about 90 movies. That means that every time I was pretending to be someone else. There comes a time in your life when you say, well, 'who am I?'" he said. "I have found writing books a good substitute to making pictures. When you write a book, you get to determine what part you are playing."

Douglas also became one of Hollywood's leading philanthropists. The Douglas Foundation, which he and Anne Douglas co-founded, has donated millions to a wide range of institutions, from the Children's Hospital Los Angeles to the Motion Picture & Television Fund.

In 2015, the foundation endowed the Kirk Douglas Fellowship — a full-tuition, 2-year scholarship — at the American Film Institute.

As a young man, Douglas very much lived like a movie star, especially in the pre-#MeToo era. He was romantically linked with many of his female co-stars and dated Gene Tierney, Patricia Neal and Marlene Dietrich among others.

He would recall playing Ann Sothern's husband in Letter to Three Wives and how he and the actress "rehearsed the relationship offstage."

He had been married to Diana Dill, but they divorced in 1951. Three years later, he married Anne Buydens, whom he met in Paris while he was filming Act of Love (and otherwise pursuing a young Italian actress) and she was doing publicity.

He would later owe his very life to Anne, with whom he remained for more than 60 years. In 1958, the film producer Michael Todd, then the husband of Elizabeth Taylor, offered the actor a ride on his private jet. Douglas' wife insisted that he not go, worrying about a private plane, and he eventually gave in. The plane crashed, killing all on board.

Douglas had two children with each of his wives and all went into show business, against his advice.

Besides Michael, they are Joel and Peter, both producers, and Eric, an actor with several film credits who died of a drug overdose in 2004.

Later generations came to regard Kirk as Michael's father. Michael Douglas not only thrived in Hollywood, but beat his dad to the Oscars with a project his father had first desired.

Kirk Douglas tried for years to make a film out of Ken Kesey's cult novel One Flew Over the Cuckoo's Nest.

In the 1970s, he gave up and let Michael have a try. The younger Douglas produced a classic that starred Jack Nicholson (in the role Kirk Douglas wanted to play) and dominated the Oscars, winning for best picture, director, actor, actress and screenplay.

"My father has played up his disappointment with that pretty good,'' Michael Douglas later told Vanity Fair. "I have to remind him, I shared part of my producing back-end (credit) with him, so he ended up making more money off that movie than he had in any other picture."

"And I would gladly give back every cent, if I could have played that role," the elder Douglas said.

Kirk Douglas' film credits in the '70s and '80s included Brian De Palma's The Fury and a comedy, Tough Guys, that co-starred Burt Lancaster, his longtime friend who previously appeared with Douglas in "Seven Days in May," "Gunfight at the O.K. Corral" and other movies.

A stroke in 1996 seemed to end his film career, but Douglas returned three years later with Diamonds, which he made after struggling to overcome speech problems.

"I thought I would never make another movie unless silent movies came back," he joked.

In 2003, Douglas teamed with son Michael; Cameron Douglas, Michael's 24-year-old son; and ex-wife Diana Douglas, Michael's mother, for "It Runs in the Family," a comic drama about three generations of a family, with a few digs worked in about the elder Douglas' parenting.

In March 2009, he appeared in a one-man show, Before I Forget, recounting his life and famous friends. The four-night show in the Kirk Douglas Theatre in Culver City was sold out.

"I've often said I'm a failure, because I didn't achieve what I set out to do," Douglas told the AP in 2009. "My goal in life was to be a star on the New York stage. The first time I was asked by Hal Wallis to come to Hollywood, I turned him down. 'Hollywood? That trash? I'm an actor on the Broadway stage!'"