If you're offering me diamonds and rust

The Present/Recent Past:

Ukiuvak is from an Earth where the Cold War's intensity led to more forced relocation of Native Americans/First Nations people into the furthest parts of the Arctic, in response to Russia venturing into and industrializing oil-rich parts of Siberia. This has led to both governments starting to realize that non-human, sentient life is in fact present on Earth, much to the horror of most non-humans. Further expansion into areas formerly only populated by non-humans has led to humans coming across more and more evidence of not being the only people on the planet; archaeologists can tell when found objects are not all that old, linguists can see when the writing found is wholly unrelated to any writing system in the area, and cameras can capture images of blurry Ieuqut figures in the distance in places normally thought to be uninhabited.

While the Cold War is the reason why more humans are in the north, obviously the north has always been inhabited. Ieuqut, Tornrait, and Qalupalik lived in the same areas as many Arctic dwelling humans for thousands of years, largely seperate from each other. Contact with humans was always limited, especially after humans began to blame non-humans for problems ranging from broken nets to murders in their villages, leading to superstition and wild speculation. Avoidance has always been the standard policy of the Ieuqut, particularly after an event a few hundred years ago where attempts by Qalupalik to negotiate peace and hunting rights led to the slaughter of nearly fifty Qalupalik people. While individual non-humans have interacted with humans without it leading to disaster, such interactions just as often went awry, historically speaking. It was simply easier to move into more and more remote places and build cities within hollowed-out mountains and hills, away from humans altogether.

Ukiuvak is distantly part human, but while intermarriage between Ieuqut and humans is not unknown historically, it's extremely rare in a historical context and unthinkable in the current era. Such marriages were rare even when they did occur generations ago; now, with human hostility at an all time high and paranoia towards them reaching peak levels among Ieuqut people, it is unheard of. Historically, intermarriages led to violence against said couples from the human side. The human partner would have to be relocated to an Ieuqut settlement in order to live in safety, or if they refused, any offspring would be taken and spirited away to an Ieuqut village or town, where they could live without fear of being killed for their powers.

The situation has always been tense. White people arriving did not singlehandedly create the paranoia that the Ieuqut communities have about being discovered and killed, they just accidentally made it worse via Arctic relocation programs and setting up research centers, as well as creating trading posts and later introducing air travel that brought more and more humans to the area. That said, they didn't improve anyone's perceptions of humankind via their fighting with and poor treatment of the local indigenous population over the years. The general impression such fighting and disputes left on the non-humans of the Arctic was that humans were at best prone to violence but loyal to their family and hard workers, and at worst violent sadists who would turn even on their own people without much warning. That's obviously not an accurate view of the human race, but a lack of real communication leads to some pretty intense misunderstandings over the centuries.

Unlike in our world, Arctic relocation and settlement by white people has been significantly more thorough, owing to a focus on obtaining the resources contained within the region. This shift in history was largely reactionary, caused by the United States reacting to Russia undertaking the same kind of operations. Currently, in Ukiuvak's world, it's 1968, and the relocation efforts have been going on and intensifying since the mid 50's, but have already long, long surpassed anything that occurred in our world in scope, effectiveness and duration. Oil rigs have been established with much greater frequency in the north, across Alaska and in Russia. Consequently, the human population is higher in Ukiuvak's world in such areas than it is in the United States - though, obviously, still low given it's the Arctic.

The Past:

How far back the Ieuqut have been in the Arctic is a subject of some debate historically. Traditional religious beliefs insist that they have simply always been there. Written records go back considerably, at least five thousand years, with many Ieuqut cities and towns having been carved into the hills and mountains so long ago that records of their founding no longer exist. The linguistic differences between groups of Ieuqut stretching from Alaska to Greenland indicates a prolonged occupation and time for isolationism and tribalism to set in, complete with differences in tradition and culture. Due to the lack of full answers for questions pertaining to the past, history is a field in which Ieuqut scholars are deeply invested even in the current day.

The area in which Ukiuvak lives, the High North, has been inhabited for around four thousand years, with the area closest to the Arctic Ocean and the Pacific Ocean being the most heavily inhabited. In all Ieuqut tribes save for the Aqiavasra, settlements are above the Arctic tree line, adjacent to an ocean, or both. Unlike the Qalupalik, another group of non-humans of the Arctic, the Ieuqut do not live on islands out in the ocean itself and do not inhabit any part of the Aleutian Islands. While Qalupalik history is oral rather than recorded via writing, their own version of history recounts the Ieuqut having been in the Arctic before they were. The Tornrait, the most technologically advanced and isolationist of the Arctic species, maintain they were in Greenland and the central Arctic prior to the Ieuqut.

Ultimately, the salient point is not who got there first. It is that over the course of thousands of years, permanent settlements by the Ieuqut have been carved into the earth and maintained for far long than anything humans have built, humans in the area largely being migratory and nomadic. Prior to the shift in human settlements, this migratory pattern kept humans' risk of interacting with Ieuqut civilization on a large scale low, as humans were often not in the same area as their non-human counterparts. This makes the problem of prolonged fear of interaction with humans a relatively new one, both historically and sociologically speaking; Ukiuvak's parents were the first generation to truly live in fear of humans discovering and attacking them, and his generation is the first to be on active patrols to maintain boundaries and secrecy.

This is why human-Ieuqut marriages were possible six generations ago, when Ukiuvak's last fully-human ancestor entered the bloodline. When humans were still nomadic, it was possible for a single human to go missing and for the humans of the region to blame bad spirits without having the resources, willpower or time to launch an investigation. That is simply not possible at this point, and as such, intermarriage has been made illegal recently for the first time in Ieuqut history. Trade between Ieuqut and humans, even disguised Ieuqut in remote locations, has been illegal for forty years. Restrictions and fear have been slowly but steadily implemented into the fabric of Ieuqut society, and the crux of the social, psychological basis for it is that the Ieuqut are the ones who made something of the land. They are the ones who tamed it, the inside of it, forging homes out of the hills.

And if that sounds incredibly dismissive towards the native humans and highly self-serving: it is. Historical revisionism is not a uniquely human trait.