Stan Lee, the legendary writer, editor and publisher of Marvel Comics, has died. He was 95. Lee, who began in the business in 1939 and created or co-created Black Panther, Spider-Man, the X-Men, the Mighty Thor, Iron Man, the Fantastic Four, the Incredible Hulk, Daredevil and Ant-Man, among countless other characters, died early Monday morning at Cedars-Sinai Medical Center in Los Angeles.

"He felt an obligation to his fans to keep creating. He loved his life and he loved what he did for a living. His family loved him and his fans loved him. He was irreplaceable." his daughter J.C. Lee said in a statement to Reuters.

Born Stanley Martin Lieber on Manhattan's Upper West Side in 1922, Lee's childhood was marked by the Great Depression. In his 2002 autobiography Excelsior!, Lee described how his father's struggle to find a steady job had forever affected him: "It's a feeling that the most important thing for a man to do is to have work to do, to be busy, to be needed," he wrote.