Stan Lee – the man behind Spider-Man, Iron Man, the X-Men, and many more has passed away at the age of 95. He was the comic book icon who created the Marvel Universe, beginning in 1961,  that we all admire. TMZ reports that after a year of declining health, including a bout of pneumonia, Lee died in an L.A. hospital.  Lee created some of the most iconic superhero characters of all time, including The Incredible Hulk, and Black Panther, along with the Avengers.

The Marvel Cinematic Universe – a multi-billion dollar firm franchise, which includes roughly 20 movies and the massive Avengers series, has become the most powerful force in Hollywood – thanks to Lee. Since the revitalization of the characters in 2010 with Iron Man, Lee’s characters landed some of the highest grossing movies of all time. In 2012, he told Esquire that his favorite part of his long legacy was seeing characters he put on paper in the ’60s become living breathing people in the movies.

“When you can sit down with a plain sheet of paper in front of you and make some notes, and, little by little, you see it take shape and become a concept for a movie or a TV show. That’s a real thrill,” Lee told Esquire. “You watch it go from notes on a paper to a meeting with writers and directors and actors. I can’t think of anything that’s more exciting.”

Stan Lee grew up during the Great Depression, being born in Manhattan in 1922, where he would write to pass time, which led to a great  American success stories. Lee turned his passion for imagination into what Esquire calls “one of the two most iconic comic book publishers of all time,” in addition to some of the most beloved characters on print or film.

“The most important thing in those days was the cover. All these books were on the newsstand, and you had to hope your cover would compel somebody to buy the book. And everything depended on the name,” he told Inc in 2009. “A character like Hurricane was a guy who ran very fast. Later on, when I was looking for new superheroes, it occurred to me that somebody crawling on walls would be interesting. I thought, Mosquito Man? It didn’t sound very glamorous. Fly Man? I went down the list and came to Spider-Man. That was it.”