In 1940, writer Joe Simon conceived the idea for Captain America and made a sketch of the character in costume.

Needing to fill a full comic with primarily one character's stories, Simon did not believe that his regular creative partner, artist Jack Kirby, could handle the workload alone: I didn't have a lot of objections to putting a crew on the first issue ...

I wrote the first Captain America book with penciled lettering right on the drawing boards, with very rough sketches for figures and backgrounds.

[6] Captain America Comics #1 – cover-dated March 1941[7] and on sale December 20, 1940,[8][9] a year before the attack on Pearl Harbor, but a full year into World War II – showed the protagonist punching Nazi leader Adolf Hitler; it sold nearly one million copies.

"[5] The threats, which included menacing groups of people loitering out on the street outside of the offices, proved so serious that police protection was posted, with New York Mayor Fiorello La Guardia personally contacting Simon and Kirby to give his support.

[11] Though preceded as a "patriotically themed superhero" by MLJ's The Shield, Captain America immediately became the most prominent and enduring of the wave of superheroes introduced in American comic books prior to and during World War II,[12] as evinced by the unusual move at the time of premiering the character in his own title instead of an anthology title first.

In response, Goodman had Simon and Kirby create a distinctive round shield for issue 2, which went on to become an iconic element of the character.

Stanley Lieber, now better known as Stan Lee, in his first professional fiction writing task, contributed to the character in issue #3 in the filler text story "Captain America Foils the Traitor's Revenge", which introduced the character's use of his shield as a returning throwing weapon.

Atlas Comics attempted to revive its superhero titles when it reintroduced Captain America, along with the original Human Torch and the Sub-Mariner, in Young Men #24 (December 1953).

Atlas' attempted superhero revival was a commercial failure,[18] and the character's title was canceled with Captain America #78 (September 1954).