In the United States many of these super powered people entered the stage and became known as Superheroes others were marked by strange deformities and became known as Freaks other terms have been used over the years but collectively they are referred to as Mutants.
The treatment of Mutants varies from country to country even though there is a League of Nations Mandate regarding Mutants.
In the United States many of these Mutants used their powers to fight crime. The various local governments and the federal government decided that the Mutants should be limited and licensed like the bounty hunters already were. Local governments were allowed to license 'Exceptional' Law Enforcement personel. Federal Law recognized the rights of properly licensed and duly sworn officers to operate outside the normal bounds of the Law, just as bounty hunters do to this day.
In 1941 President Teddy Roosevelt sent out the call for a new model of US Military incorporating Mutants to counter the Axis' SS Special Units and the Emperor's Own Samurai. The Stalin had Purged all of the USSR's known Mutants and the SS Special Units nearly captured Moscow before the entry of the Allies.
The Mutants were found in every branch of the military. The highest ranking Mutant ever was Marine General Lloyd Williams he was a Mutant who survived the battle of Belleau Wood.
A Note on Costumes:
Costumes became worn during the early years when many Mutants exhibited their powers and abilities on the stage and screen. When laws went into effect to allow for the 'Exceptional' law enforcement the costumes became accepted as uniforms by many authorities.
By the 1920's and 30's the public had become so used to the idea of Superheroes wearing costumes that many new Mutants thought nothing of donning a mask or cape. Like all apparel costumes have gone through phases of fashion currently they are in fashion but who knows what tomorrow may bring?
X-Men not of this world is not 'canon' X-Men history. The game is set in an alternate universe where Mutants exist but the comics and movies are considered fictional dramas. Players are free to create characters based on canon characters or new character concepts.
