Tales of Suspense #39 Iron Man First Appearance (Marvel, 1963)

"Iron Man Is Born!" This story title does not overstate it at all! It was just two years into the nascent Marvel Universe, and this was the month that it all started to come together. The FF appeared in The Amazing Spider-Man #1 and Iron Man made his debut in this issue. Decades later, of course, Iron Man would become the tentpole of the Marvel Cinematic Universe, and this very story would be retold in his first film in 2008. With Tony Stark's notable influence in creating the Avengers showcased in both comic books and the movies, he (and his armored alter ego) became cornerstones of both universes.
This splash page from his first appearance really captures the power of the character. As technology raced forward in the early 1960s, Iron Man began to seem more and more plausible, and Marvel kept the character at the forefront of innovation through a steady stream of upgrades and advances to his armor (even if that sometimes meant talking about "transistors" a lot). But this is where it all began, with the original "Old Grey" version of the Mark I (Model 1) armor!