Stan Lee, the cultural icon responsible for many of Marvel’s most popular superheroes in comic books and movies, died at the age of 95.

Lee died Monday at Cedars-Sinai Medical Center in Los Angeles, according to Kirk Schenck, an attorney for Lee's daughter, J.C. Lee. Lee’s POW! Entertainment company confirmed the news to USA TODAY.

"His passing today marks a devastating and painful moment in time, but the legacy of Stan Lee, through his creative genius and his universes of characters, will continue to reach the world of true believers for generations to come," POW! CEO Shane Duffy said in a statement. He called Lee "the father of pop culture."

Born Stanley Martin Lieber, the New York City native co-created Spider-Man, Hulk, the Avengers, the X-Men, the Fantastic Four, Black Panther, Daredevil, Doctor Strange and a host of other heroes while working as a writer, then editor-in-chief of Marvel Comics in the 1960s.

From the 1970s (when he became publisher) until the ’90s, Lee was the face of Marvel and a frequent staple at comic and pop culture conventions, entertaining fans and “true believers” with his stories and signature catchphrase, “Excelsior!” He created his own POW! Entertainment in 2001 to develop film, TV and comic properties but always stayed connected to his original superhero roots as geek culture rose in Hollywood.

Though Lee’s infectious enthusiasm for his heroes – and his devotees – lasted late into a legendary life, recent years were marked by ill health and legal wrangling involving those closest to him. After the death of his wife of 69 years, Joan, in 2017, Lee was hospitalized in February 2018 for an irregular heartbeat and shortness of breath, and he struggled with pneumonia. In March, Lee reported $1.4 million stolen from his bank account. In April, he sued former business manager Jerardo Olivarez for alleged fraud and elder abuse, then a month later filed a $1 billion fraud suit against POW!.

Lee denied signing a document in April 2018 stating that daughter J.C. Lee and friend/business manager Keya Morgan were trying to gain control of his assets and property. Morgan had a restraining order against him during a Los Angeles police investigation of elder abuse against Lee.

Lee was a progressive force in his chosen medium. He tackled prejudice and intolerance in his "Stan's Soapbox," challenged the obsolete Comics Code Authority with a 1970s anti-drug story line in "The Amazing Spider-Man" and introduced Black Panther, an African king and great scientist, the first major black superhero in comics.

"I wanted to go against type," Lee said. "Even though he had a little thatched-hut village in Africa, that was only to fool people. Underneath that, he had this modern civilization.

"I always felt at Marvel, we had to do things different. The reader had to be surprised and had to be meeting characters the likes of which he or she hadn't met before."

When fans asked, Lee said Spider-Man was his favorite heroic creation, mainly because of his Everyman nature.

"You feel you know him. He's not just a cardboard figure with a lot of muscles," said Lee, who served in the U.S. Army for three years during World War II, first as a member of the Signal Corps, then as a "playwright" in the Training Film Division. Lee's last tweet before his death was a Veterans Day message thanking fellow vets for their service.

For Lee, his heroes always were meant for much more than being on the comic book page. He moved from New York to Los Angeles in 1981 to develop Marvel movies and TV shows, and he narrated cartoons such as "Spider-Man and His Amazing Friends." Lee and fans had to wait nearly 20 years to see the big-screen potential of these characters.

Lee was also able to see them up close – he had a cameo in nearly every Marvel movie, beginning with Bryan Singer's "X-Men" in 2000.

There was nothing more fun for him than stealing a scene in a blockbuster movie, Lee said in 2014. "It doesn't require a lot of rehearsal, you get there, you do it, you get the hell out of there in a few minutes, and you're on the screen forever."

Contributing: The Associated Press.

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