The Tarim mummies, in the bigger picture, were merely the last breath of the proto-Norse peoples in north-central Asia. I would place the original home of these proto-Norse peoples in about what is modern Kazakhstan; and if we were to follow Bal Gangadhar Tilak's true hypothesis in 'The Arctic Home in the Vedas', then it may have even existed along the Kara Sea in northern Eurasia. It's even conceivable that the ice cap covered part of this northern sea, and some people may have lived above above it. At the least, some people could have lived along this northern coast and would have literally lived slightly above the Arctic Circle. If this were true, then Tilak's hypothesis surrounding the Vedic hymns could be proven true scientifically.
The ice sheet (see map), even at the height of the last ice age, covered the British Isles and about half of central Europe. However, when it reaches about Russia, it directs northward and the Eurasian ice cap ends in the middle of the north coast of Asia. It's very possible that people could, as Tilak hypothesized, have lived up there. Also, the last glacial movement was about fifteen-thousand years after the height of the last ice age. It's very likely that it was comparatively even more habitable then.

Another possibility is that they were trapped up there. Look at the map again, there's quite an uneven ice sheet. Regions far north were more habitable than regions further south, and it's possible that an ice sheet may have left a large "island of habitable land" which was enclosed by ice sheets. When the book was published a century ago, many people probably dismissed it because it was too groundbreaking for it's time. In other words, the Tarim mummies were not from northern Europe; they were home. They were the last remnants of the ones who stayed behind. Fifteen or twenty thousand years ago, the proto-Norse or proto-Germanic people may have all lived in a habitable region in northern Eurasia, enclosed by sheets of ice. The Eurasian ice sheet to the west, and the Himalayan ice sheet to the south.
If they did live way up there, then we need only to look at the Eskimos for some idea of how they could have survived. Also, there is a lot of meat and fur on a woolly mamoth, a woolly rhinoceros, or a yak; and they were roaming all over that tundra back then. I would guess that those pure proto-Norse were tall, strong, white-skinned, had very light blonde hair, pale blue eyes, straight noses, and generally the physical Scandinavian stereotype. Only much later--amid the melting ice of post-ice age Europe--when they encountered the native Alpine peoples, did more slightly tanner, ash blonde haired, basic-blue eyed people come about; and of course, combinations closer to the Alpines. Still today, we can occasionally see people who are extremely-fair "throw backs."
During the 1938–1939 German expedition to Tibet, I believe that they were looking for "The Arctic Home in the Vedas." The Tibet Autonomous Region, which is twice the size of modern Tibet, may have seemed like the most logical area to look at. That highland region was probably largely covered by the Himalayan ice sheet or at least a harsh landscape up to about ten-thousand years ago. I believe that ancient Kazakhstan, and probably north of it, is the logical location of the age old question of where is the location of the original homeland of the Aryan people. However, they weren't "Aryan" then.
The Aryans came about in ancient Persia, when some of the migrating proto-Norse encountered native or migrating true-Mediterranean (not Semitic) peoples. Among many technological advances and spiritual concepts, the Sanskrit language and text developed from these Aryans of ancient Persia. The ancient Swastika, which was originally a solar symbol and spiritual symbol of geometry and mathmatics, was brought by the true-Mediterraneans into ancient Persia. Similar symbols developed in different locations, so I think this is still an unanswered question. It's pretty easy to see how all of this has been so confusing, to so many, for so long.
To make it easier to understand, this "Aryan hypothesis" seems to have basically involved only three racial/sub-racial types. Two who were collectively to become "European" at a later incarnation, proto-Norse and true-Mediterraneans, and the native people(s) of India. This was at a time long before Mongol, Semitic, and Turkic expansion. Civilization was founded by true-Mediterraneans in Sumeria, and expanded around the general area of the ancient Middle and Near East. When some of them migrated to the high mountainous plateau of ancient Persia, they encountered some of the proto-Norse migrating from the north. They blended into a special kind of civilization. The science and technology of the true-Mediterraneans, and the language and earth-based spirituality of the proto-Norse.
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There are a lot of terms and concepts in regard to "the Aryans"; and to add to the confusion, they overlap linguistically, culturo-spiritually, and to a lessor extent: ethnically.
Indo-European
In the above link, you will find a maze of terms and ideas which basically boil down to "Indo-European" being a "language family" with a common linguistic origin. Amazingly, this "language family" extends from Iceland to Sri Lanka.
It should be noted that this tie-in would not include Mongol, Semitic, or Turkic peoples; all of whom expanded at a later time period. That should lessen the confusion a bit; and it should also be noted that the English, Spanish, Portuguese, and Arabic languages all have speakers among them who are from all of the races of the world. Now if we consider that most of the ancestors of the Icelanders lived in the Ice Age Middle East over 20,000 years ago; then this linguistic tie-in becomes less of a radical idea... at least believable.
Indo-Iranian
We should never confuse "Persian" with "Arabic," even if most are Muslim. Despite the despotism of the Mullahs today, very few are "radical Islamists." After the proto-Norse moved on, ancient Mediterraneans occupied ancient Persia, perhaps followed by a long connection with India; but Arabic, Mongol, or Turkic influence was genetically small.
I once saw an image online of a Persian man, perhaps in his forties, wearing a Kaftan of some type; who looked like a Norwegian. Not just because of his blonde hair and blue eyes, but all of this facial characteristics were Nordic-like. He had a thick blonde beard, deep eyes, straight nose, pronounced forehead, etc. If he shaved his beard, and dressed in Western-style clothing, he could walk down any street in Scandinavia unnoticed. It should be noted that the Iranian president, Ahmadinejad, is of a particular Semitic-type, and not a typical Persian.
This linguistic category is regional, but tied into the larger language family. It is also referred to as the "Aryan languages." It's present geographic range extends from eastern Turkey, Iran, Afghanistan, most of India, and Sri Lanka; or in other words "the eastern Indo-Europeans languages." I'm trying to stick with the linguistic aspect of this; but there are all sorts of cultural, religious, and ethnic overlap since the days of the original Aryans.
This isn't to say that the "original Aryans" were the Ice Age proto-Norse. That would be an oversimplification of this. Apparently, the proto-Norse who stayed behind as the weather grew warmer, strongly influenced more eastern peoples as far as language. As far as "the Aryan invasion of India," certainly someone invaded and influenced them. As to who exactly they were, I don't really know. Perhaps a later Persian-type of Aryan. Many of them likely had light hair and eyes at that time; which may explain some of the old accounts. That seems as good a theory as any.
"Aryans" (see Aryan, Indo-Aryan, and Aryan race)
Could it be that the ancestors of Ice Age proto-Norse who remained in the Middle East long after the tribes had moved on, then merged with early Mediterranean peoples (to form the "original Aryans?"), whose much later homogenized descendants invaded India and influenced it (mainly linguistically)? They seemed to have strongly influenced their spirituality as well. This logical hypothesis would not exactly fit either the preference of a Germanic or an Indian nationalist or idealist. However, doesn't it seem more logical than what they have offered?
It should be noted that these hypothetical proto-Mediterranean-Norse "Aryan" invaders would have looked like most Europeans today. It should also be noted that the Persian people of today would only be partly, perhaps mostly, descended from these "original ancient Aryan people." This could also explain why certain Odinic concepts appear similar to some Hindu traditions. Wikipedia: The term Aryan originates from the Sanskrit word ārya, in origin an ethnic self-designation, in Classical Sanskrit meaning "honourable, respectable, noble."
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Just to give some background--part fact, part theory--the proto-Norse during the last Ice Age, lived approximately in what is today Iran. That land looked very different 25,000 years ago. There was an ice cap a mile high above the 45 or 50 degree latitude in the northern hemisphere. Now if you look on a map, that would make "ancient Iran" and the surrounding territory into something of an Alaska! A totally different environment: dim, cold, mountainous, wooded. A harsh land of wood and snow, with whoolly rhronoceros, mammoth, and lion. These proto-Norse were not specifically "European" then; although this is part of "the Indo-European story."
"Apparently the belief (earth-based/month-birth classification system) is mainly a Norse conception, since it was the Nordic peoples, of all the ancients, who most clearly expressed their ideas in Nature. Some authorities assert that it comes from the East, whence comes all mystical lore. But since modern scholars now prove the Norse tribes to have migrated from Asia, originally, there may easily be a common origin of ideas. Certain it is that, far away in the dim ages of our nation's (UK) dawning, when wandering Aryan tribes, said to have come originally from the plain of Iran, in Central Asia, swarmed over and settled in Northern Europe, they found their ideas of God in Nature."
--Margaret Baillie-Sanders (UK), 'Your Birthday Month and You', 1932
Numerous authors and researchers--including Guido von List--who studied and wrote about subject matter basically dealing with Odinic-type spiritual traditions, eventually drifted off to other cultures to the south and east, and to India. It's as if there's a loose concept that the roads to all pre-Christian spiritual traditions, of the "earth island" and beyond, lead to ancient India. Some people believe that there once existed "mystery schools" which once tied together ancient wisdom from England to India. I don't believe that; but I think there could have been geographically smaller spiritual tie-ins between east and west, and which vibrated outward over thousands of years.
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