Stan Lee, former editor-in-chief of Marvel Comics and co-creator of the lion’s share of the company’s most successful characters (including Spider-Man, Daredevil, the Fantastic Four, the Hulk, Dr. Strange, Black Panther, the X-Men and many more), passed away early Monday morning at Sinai-Cedars Medical Center in Los Angeles. He was 95-years-old.

Lee, whose cameos in nearly every Marvel movie imaginable introduced him to a whole new generation of comic book fans, can be credited with much of Marvel Comics’ success during the 1960s, a period in which Marvel eventually overtook longtime rival DC Comics as the most popular comic book publisher and established the paradigm for realism-infused comics as we know them today.

“The characters would be the kind of characters I could personally relate to,” Lee said in Origins of Marvel Comics. “They’d be flesh and blood, they’d have their faults and foibles, they’d be fallible and feisty and — most important of all — inside their colorful, costumed booties they’d still have feet of clay.”

According to the Associated Press:

Some of Lee’s creations became symbols of social change — the inner turmoil of Spider-Man represented ’60s America, for example, while The Black Panther and The Savage She-Hulk mirrored the travails of minorities and women.

Remembering Stan Lee:

Bob Iger, Chairman and Chief Executive Officer, The Walt Disney Company:

Stan Lee was as extraordinary as the characters he created. A super hero in his own right to Marvel fans around the world, Stan had the power to inspire, to entertain, and to connect. The scale of his imagination was only exceeded by the size of his heart.

Dan Buckley, President of Marvel Entertainment:

Stan Lee’s passion, charisma, and his love for the characters and stories he created shaped Marvel into what it is today. His relentless drive and dedication to tell imaginative stories changed the lives of countless fans for over 75 years, and his spirit lives on in the people he’s inspired. His legacy will never be forgotten. My thoughts go out to his family at this difficult time.

Kevin Feige, President of Marvel Studios:

No one has had more of an impact on my career and everything we do at Marvel Studios than Stan Lee. Stan leaves an extraordinary legacy that will outlive us all. Our thoughts are with his daughter, his family, and the millions of fans who have been forever touched by Stan’s genius, charisma and heart. Excelsior!

Lee is survived by his daughter, Joanie, and a younger brother, Larry Lieber, who also worked in the comics industry. Our thoughts and prayers go out to Lee’s family and loved ones — the world has lost a comic book genius and icon today.