Why do you think the uncle was named the “Unnatural Uncle” ?

The pronunciation of Eskimo names are impossible so the author decided that this was easy for the reader

The Eskimo’s felt that family was important and to try to harm a family member was not normal or natural

All Eskimo myths name the antagonist the “Unnatural Uncle”

Since this tale is from the oral tradition, the characters had no names and when the myth was written down this is the name that was given