<P> Al Liederman would ink that first issue, which was lettered by Simon and Kirby's regular letterer, Howard Ferguson . </P> <P> Simon said Captain America was a consciously political creation; he and Kirby were morally repulsed by the actions of Nazi Germany in the years leading up to the United States' involvement in World War II and felt war was inevitable: "The opponents to the war were all quite well organized . We wanted to have our say too ." </P> <P> Captain America Comics #1--cover - dated March 1941 and on sale December 20, 1940, 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 . While most readers responded favorably to the comic, some took objection . Simon noted, "When the first issue came out we got a lot of...threatening letters and hate mail . Some people really opposed what Cap stood for ." 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 . </P> <P> Though preceded as a "patriotically themed superhero" by MLJ's The Shield, Captain America immediately became the most prominent and enduring of that wave of superheroes introduced in American comic books prior to and during World War II, as evidenced by the unusual move at the time of premiering the character in his own title instead of an anthology title first . This popularity drew the attention and a complaint from MLJ that the character's triangular shield too closely resembled the chest symbol of their Shield character . 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 . With his sidekick Bucky, Captain America faced Nazis, Japanese, and other threats to wartime America and the Allies . Stanley Lieber, now better known as Stan Lee, 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 . Captain America soon became Timely's most popular character and even had a fan - club called the "Sentinels of Liberty". </P>

When did the first captain america come out