He was born Jacob Kurtzburg on August 28, 1917 in New York City. He worked for Fleischer Studios from 1935 where he did in-betweens for Popeye animated cartoons. He joined the Lincoln Newspaper Syndicate in 1936 and worked for them until they went out of business in 1938.
Kirby met Joe Simon while he was producing freelance work for a variety of publishers. The two young men teamed up and began producing packaged comic books for sale to publishers. The duo created the patriotic hero Captain America for publisher Martin Goodman in 1941. Kirby's dynamic perspectives, ground-breaking use of center-spreads, cinematic techniques and exaggerated sense of action made the title an immediate hit and rewrote the rules for comic book art.
The Simon & Kirby name became synonymous with exciting superhero comic books. They reinvented the pulpish Sandman strip in Adventure Comics to emphasize a more superheroic bent.
As superhero comics waned in popularity after the end of World War II Kirby and his partner began producing a variety of other genre stories. They are credited with the creation of the first romance title, Young Romance Comics. In addition Kirby and Simon produced crime comics, horror comics, westerns and humour strips.
The Kirby & Simon partnership ended in 1954 with the comic book industry beset by self-imposed censorship and negative publicity. Kirby continued to create comics reinventing the Green Arrow strip in Adventure Comics and creating the well-received classic about a group of death defying adventurers, the Challengers of the Unknown.
Kirby returned to Marvel Comics where he produced a series of imaginative monster, horror and science fiction stories for its many anthology titles. Kirby's bizarre designs of powerful unearthly creatures were a hit with the reading audience. At the behest of publisher Martin Goodman and together with partner Stan Lee, Kirby began creating superhero comics once again in 1961. He had a hand in the creation of nearly every character for Marvel for the next several years. Some of the highlights include such characters and concepts as the Fantastic Four, Thor, the Incredible Hulk, Iron Man, the X-Men, the Silver Surfer, the Avengers, Doctor Doom, Galactus, Adam Warlock, Magneto, Fin Fang Foom, the Mad Thinker and his Awesome Android, the Red Ghost and his Super-Apes, the Inhumans, Wakanda, the Black Panther, the Blue Area of the Moon, Kang the Conqueror, the alien Skrulls, Daredevil, the Impossible Man, the Molecule Man, Paste-Pot-Pete, the hidden city of Attilan, Asgard, Hel, and the Negative Zone among many others.
After a falling out with Stan Lee, Kirby returned to DC in the early 1970s where he produced a series of titles under the blanket sobriquet The Fourth World. The titles he produced included The New Gods, Mister Miracle, and The Forever People along with such other unique books such as OMAC, Kamandi, The Demon, and a new incarnation of the Sandman (this title together with former partner Joe Simon for one last time).
He later returned to Marvel Comics where he returned to Captain America to both write and draw the title. His other Marvel creations in this period included Devil Dinosaur, The Eternals, and a comic adoption and expansion of the film 2001: A Space Odyssey. He eventually left the company again to go to Pacific Comics where he began the series Captain Victory, which took the then unusual step of Kirby retaining copyright over his creation and received royalties on it. This in turn began a precedent that helped other talents strive to receive similar consideration for their work in comics.
Kirby is popularly acknowledged by comics creators and fans as one of the greatest and most influential artists in the history of comics. His productive output was legendary as one count estimates that he produced over 25,000 pages during his lifetime as well as hundreds of comic strips and sketches. He also produced paintings, and worked on numerous concept illustrations for a number of Hollywood films.