Patriotic superhero created by Joe Simon and Jack Kirby…

Patriotic superhero created by Joe Simon and Jack Kirby, who debuted in 1941 on a comic book cover showing him punching Adolf Hitler. Steve Rogers, a frail young man rejected by the army, becomes a super soldier after receiving an experimental serum. Armed with a round shield bearing a star, he fought in World War II, was frozen in ice for decades, and later joined the Avengers as their leader.

The answer in 14 letters