Marvel has not officially stated why mutant populations APPEARED to be greater in the European and Western world than they do in the rest of the planetary populations.
- The answer could be as simple as the writers, being Western focused on Western culture and wrote about mutants in those cultures first. Later writers becoming more aware of their cultural bias, expanded the range of mutants so they appear in most civilizations in varying densities.
While the first mutants discovered by Xavier were mostly white and from the United States, later mutants would hail from a variety of cultures and locations around the world including, Native Americans, the Soviet Union, African, Germany, Ireland, Australia and Japan.
Given there was little internal logic being directed toward mutant populations in the Marvel Universe before M-day, all we can offer is speculation based upon cultural, social, environmental and technological possibilities in the Marvel Universe.
- While what I call Celestial Gene Tech (CGT) was applied to the three subspecies of humanity, the Eternals, the Deviants and mainstream Humanity, we are not given any proportions to how much of said CGT has been applied in what proportions to humanity as a whole.
See Also: Are the mutations in the Marvel Universe that were created by Celestials only able to be created by Celestial technology?
If we are to assume that most of humanity owes its existence to Mitochondrial Eve, then the CGT would be evenly distributed and should exist in all populations relatively equally and larger populations should have greater numbers of mutants proportionally.
Later experimentation by the Kree also affected a wide array of Human and Inhuman populations distributing Kree-gene tech (KGT) making Inhuman/Human hybrids vulnerable to their genetic triggering mechanisms using mechanisms such as the Terrigen mists.
Such KGT may have altered mutant population densities since the Inhumans were inclined to keep their existence secret and random mutation near their hidden enclaves might lead others to discover their secrets. The Inhumans may have been responsible for keeping extreme mutant populations from reaching a serious threshold in any area near them. (For most of their history they were in the Himalayas which may explain why there are less mutants in that region.)
However, there are several forces which have been reputed to have manipulated the number of mutants in human history, with those forces including:
- More powerful mutants: Apocalypse was known to prey upon weaker mutant on the African subcontinent, weeding out what he deemed to be weaker mutants, either enslaving them or destroying them. Other such manipulators include the Externals, immortal mutants whose extreme power levels may have lead them to destroy potential competitors. Not to mention mutant scientists such as Nathaniel Essex (Mister Sinister) who has spent centuries experimenting upon and manipulating genetic families for his own unknown purposes.
Time travelers: Kang/Immortus (and many others) made trips to the past manipulating humanity for unknown reasons, as well as entities such as the Sphinx and the Stranger who manipulate creatures who interest them for unknown purposes.
Nefarious extra-dimensional or immortal entities: beings such as Selene, Mephisto, Dormammu, and Zarathos seeking powerful hosts capable of forwarding their agendas. Such beings are completely capable of using mutant capacity, particularly those with energy manipulating powers as conduits for them to enter into our dimension.
Selene is considered to secretly be the very first human mutant or at least the oldest living by those-in-the-know, her millennia-long life is attributed to the fact that she is a 'psychic vampire,' able to drain lives of others in order to extend her own. Her name derives from the ancient lunar deity Selene, daughter of the Titans Hyperion and Theia.
Claiming to have already been old when modern mankind was just emerging, Selene was born over 17,000 years ago somewhere in what is now Central Europe, "after the Oceans swallowed Atlantis and before the rise of the Aryas". Her tribe's elders recognized her for what she was and commanded the entire tribe, including her own mother, to sacrifice their lives to feed her.2
Such beings may have become legendary beings or threats to be put down by heroes of previous eras or even the Eternals who have spent thousands of years being mistaken for the Greek/Roman deities in the Marvel Universe.
- Other Divine/Infernal entities may have collected/harvested such beings (as Gaia did holding them in abeyance until the arrival of the Celestials in the Fourth host) as examples of superior genetic qualities sought by the Celestials. They may have also been destroyed by the pantheons of Earth if they could create conditions which would endanger life on Earth.
(Thor I#300-301) – Just before Arishem the Celestial committed a deathblow to Thor, Gaea appeared to save him and presented the Young Gods to the Fourth Celestial Host, which resulted in their judging in favor of Earth.
Secret societies or civilizations such as the mystical city K'un-Lun in the K'un-Lun Mountains (崑崙山) may have been training areas for such early mutants hiding their populations within their specialized regions. Hidden in one of the longest mountain chains in Asia, mutants may have been absorbed into this population as well as becoming nemesis for the city for millennia. Organization such as the Hand may also be responsible for enlisting, recruiting or destroying mutants they could not swing to their causes.
Extradimensional mutants such as Nightcrawler's father Azazel claim that many years ago an ancient horde of demonic humanoid mutants from biblical times called the Neyaphem were in an epic battle with a group of angelic xenophobic mutants, named the Cheyarafim. The Cheyarafim were victorious in the battle and banished the "demons" to an alternate dimension for all eternity. The Neyaphem's leader, Azazel, was the only one who was able to breach the dimensional void for brief periods of time due to his teleportation powers. His only hope to return to Earth was by impregnating women because his children are linked to his dimension
Members of the Neyaphem, mutants from over 6,000 years ago engaged in a battle with the Cheyarafim were exiled to an extradimensional realm but originated on Earth.
Other Limits on Mutation in the Marvel Universe
Technological trigger limiters: Marvel has given no indications of the rate of mutation overall, (estimates made the potential population of mutants to be in the millions) but it was hinted that such powerful mutations occurred at a lesser rate in the past than in the present. Which would make sense if the genetic markers were designed to trigger a particular event which might require later technological changes in society to take place. If mutation required exposure to radioactive materials, for example, then we might only see mutants in areas whose natural radiations would be higher than the background radiation overall.
If this was the case, in the modern era, with a wider array of opportunities to be exposed to radiation from mundane sources (X-rays, microwave radiation, nuclear power plants) as well as nuclear weapons use and testing and radioactive sites, this could possibly be one explanation for an increase in mutation. More mutagens due to chemicals, radiation, toxic wastes could also be triggers to bringing more activity from the CGT as technology increases, so would the number of mutants worldwide.
Fear and the Nascent Mutant Vulnerability: If this is the case, then the first reason there may be fewer indications of mutation could be a social one. If mutations appeared in a superstitious population (which could apply to almost all of early humanity) the earliest manifestations of it would have likely been killed as soon as the power appeared, especially if it came with gross physical defects. If what we see with mutants at Xavier's School most mutants, even the incredible powerful ones start with periods of vulnerability. Such fear and superstition is liable to be the first and number one methods of reducing mutant populations in cultures where such things are looked at as abominations.
The origin of Nightcrawler shows his early days as an acrobat before being turn upon by his countrymen in Giant-Size X-Men #1 (May 1975).
- Predation by other Mutants/Entities: Known mutants such as Proteus and the entity known as Selene were known to prey on other mutants, feeding upon their physical or psychic essence to drive their own mutant powers. Other such predation could have existed over the ages which may have also reduced the number of standing mutants.
Magneto battles the reality-shifting Proteus stripping apart his electromagnetic form.
Proteus was a mutant that possessed a vast psionic ability to manipulate and alter reality. He existed in a state of pure psionic energy and could take possession of human bodies that his energies eventually "burned" out, killing them (including his own original body). Proteus also possessed telepathic abilities. Learning he could take over mutant bodies as well as humans he discovered mutants lasted longer and could bear the use of his reality altering powers better.
His reality manipulation powers allow him to transmute matter and bend the laws of physics according to his imagination within a certain range. Using this power he can easily turn a building into liquid, turn a vehicle into bees that attack at his mental command, transform energy into matter, manipulate weather, or strip a person of their mutant powers. He often reverses local gravity, opens fissures in the earth, and stretches people painfully into liquid shapes (they return to normal when he no longer concentrates on manipulating their bodies).
Destruction or creation by modern governments: Given the power mutants possess, it could be that primitive governments who were not able to harness mutant powers may have mandated their destruction since such beings could become a threat to the power structures. Such mutants, if they could not be recruited were likely tortured and their entire family lines exterminated. Modern governments with the knowledge they currently possess may be trying to engender new mutations or genetic technology based in CGT along with modern experimentation such as the super-soldier serum used by Captain America.
Secret assimilation into governments: Given the Hellfire Club's mandate of recruiting and empowering mutants, it is possible other cultures mutants may be hiding in plain sight as part of their respective governments using their powers to further their countries national agendas. This may have been the case at least until the recent Terrigenesis event which threatens all active mutants on Earth.
Genosha Concept Art from Deadpool Video Game by Jose Emroca Flores
One of the only times the Marvel Universe gave any solid numbers on mutants was during the Genosha Saga which indicated there were at one point, at least 16 million known mutants on Earth and living within the borders of Genosha which was acting as a sympathetic homeland for mutants before it was destroyed by Cassandra Nova.
Genosha is a fictional country appearing in American comic book series published by Marvel Comics. It is an island nation that exists in Marvel's main shared universe, known as "Earth 616" in the Marvel Universe and a prominent place in the X-Men chronology. The fictional nation served as an allegory for slavery and later for South African apartheid before becoming a mutant homeland and subsequently a disaster zone. The island is located off the Southeastern African coast northwest from Seychelles and northeast of Madagascar. Its capital city was Hammer Bay.
By New X-Men #115, Genosha had a population of sixteen million mutants and a stable, advanced society. However, the entire island was reduced to rubble and its mutant population was slain by Cassandra Nova's Wild Sentinels. There were few survivors, many evacuated, and the Brotherhood of Mutants turned one of the Sentinels into a memorial statue in #132.
In Summary
Given the number of potential threats, predators, extraterrestrial and extra-dimensional entities which were involved with Human development for the last 17,000 to 20,000 years ago, it is possible mutants were both evenly spread out over the Earth but were involved in any number of events which could have led to an uneven distribution over time.
With a wide array of diverse groups, both known to the Marvel Universe and as yet unknown ones, it is possible mutants were involved in the development of the world in ways as yet untold.
Mutant predators such as Selene who have existed before recorded history could have also taken their toll upon mutant populations with her incredible powers and experience making her an almost inescapable threat, mutants may have banded together for protection or gone into hiding to prevent from falling victim to her.
Ultimately, mutants with CGT or Inhumans with KGT embedded in their genes will likely continue to exist for the foreseeable future as Marvel works out its licensing issues and will return to the Marvel Universe in manageable numbers, likely with little consideration toward how or why their populations are what they are. What I offer here are potential reasons such disparities could exist despite the lack of awareness on the part of Marvel's writers or editors.
See Also: Is there a set limit on mutant abilities, where they're deemed too unrealistic?