[Tor3]

As vintermann said - there's no evidence for any group arriving earlier than any others. We know that the "Norwegian" population in modern Norway are a mix of the original European population and the Yamnaya and others, we don't know exactly when that population overtook the earlier one (what's certain is that people who lived along certain parts of the coast 11k-12k years ago didn't have any Yamnaya connection, obviously). We don't really know much, except that the Sami languages haven't diverged enough from related languages elsewhere for them to have been there that long ago. The Sami came much later than the post-glacial original population. When the ancestors of modern Norwegian and Sami groups (and others) arrived we simply don't know for certain. If you look at the very oldest writings you'll find that there were a great many different groups of people in Norway, including in the far north-east, and there was trade. That lasted all the way up to the arrival of Christianity, after that this (if related, or just a coincidence) became more of a "take, don't trade" business.