@Supermaxx's Superboy is APPROVED!
As with most things, it all began with an attempt to grab untold power. In the case of World War II, while most believe that the largest conflict was driven by the maniacal desires of Adolf Hitler and his Nazi regime, the truth was carefully hidden by the world's governments in an attempt to control the outcome of the war. It was Johann Schmidt, better known as The Red Skull, that sought to control the fates of entire galaxies for himself, unwilling to remain limited to the confines of his own time. And with the once mythical Spear Of Destiny just a breath away from his grasp, thanks to the machinations of time-traveller and HYDRA loyalist Per Degaton, Schmidt almost succeeded in bending the universe to his will for all time.
But there came a force unlike any before it, united in their combined will to see freedom prevail over the Skull's threat of enacting eternal cruelty.
Led by Captain America, who was once the feeble patriot Steve Rogers, a group of costumed adventurers - with a roster bolstering such heroes as The Flash, The Sub-Mariner, Hourman, Black Marvel, Green Lantern and The Human Torch, among others - eventually defeated the fearsome might of HYDRA and sent The Red Skull fleeing across Europe. While a climactic battle between Rogers and Schmidt would see both men seemingly lose their lives over the arctic, the champions of virtue that Rogers had inspired eventually returned to the United States and formally began The Justice Society Of America. But the US government had other plans for these supposed "super-humans".
Under orders from President Roosevelt, the Strategic Science Reserve - later becoming the espionage organization S.H.I.E.L.D - would begin a series of lengthy and highly classified investigations into the members of the JSA. Discovering that some of their amazing powers were in fact real, with a number of them being acquired in either freak accidents or happenstance, then-incumbent President Truman ordered that these self-styled vigilantes be brought in for questioning and otherwise contained. Rather than face public scrutiny, as was threatened with a potential inquiry into their abilities and personal identities if they refused to comply, the Justice Society disbanded and their members forcibly retired.
For over seventy years afterward, the idea of individuals with superhuman abilities and powers were turned from a prospective source of hope into a horrifyingly effective fear-mongering campaign against the already disenfranchised. Thanks to the efforts of men like Senator Robert Kelly, the evangelical military general William Stryker, and the superhuman hunting organization A.R.G.U.S., paranoia against those with metahuman powers was specifically targeted towards mutants, a sub-set of genetically gifted youths that began to appear as part of a natural state of evolution in those born with the X gene. A few outwardly spoke on behalf of mutant rights, such as Professor Charles Xavier, but their efforts were ignored. And when the mutant terrorist group known as The Brotherhood began to attack humans as a result of worldwide bigotry towards their kind, the argument in favor of their existence was seen as being made irrelevant.
In modern times, mutants were relegated to either being hidden within highly secretive families, smuggled into the night by shadowy forces working in coercion with the world's governments, or given asylum on the isolated and hidden island of Genosha. Though conspiracy theorists allege that mutantkind will eventually rise up to try and usurp humans as the primary species, these claims were largely mocked by the media and outright forgotten by the time of another bombshell in the year 2017: the discovery that we are not alone in the universe, as revealed by the arrival of a particular individual in Metropolis.
But while vigilantes that would later become known as Superman, The Batman, Wonder Woman, Aquaman, and others began to operate in a similar fashion to the JSA before them, even banding together as a group called The Justice League, S.H.I.E.L.D. began to move pawns across their own chessboard within the world of anonymous metahuman heroics. Putting together a strike team under the codename of The Avengers Initiative, Colonel Nick Fury brought together the talents of genius billionaire philanthropist Tony Stark, the supremely powerful Thor Odinson, the highly unstable Bruce Banner, and the scientifically gifted husband and wife team of Hank Pym and Janet Van Dyne to fight the battles that "we never could". And with the discovery of the miraculously preserved Steve Rogers in the arctic, Fury would ensure that Captain America would take up leadership of The Avengers in a bid to establish them as Earth's Mightiest Heroes.
With superhumans becoming a permanent fixture in Earth's culture following The Man Of Steel's debut, the last five years have been quite transformative for society at large. While the efforts of these individuals have saved countless lives, many others have been inspired to fight against them as enemies. In the crosshairs of their escalating battles, humanity has begun to question whether superhumans have a right to operate with impunity - and who could possibly stop them if they should decide to turn against the rest of us.