The native Americans at the time did claim ALL of the land settled by the European immigrants. You probably don't remember that a $24 payment was made in New York, and that the immigrants in the PLymouth colony was literally living on land owned by the native people thare, and those natives saved the lives of those immmigrants.The native nations may not have been written down on paper maps, but the people knew which land belonged to which tribe, and just because there were open places, unoccupied, it was still immigration. If all the immigrants crossing the southern border, or flying in and overstaying their visas decided to live in the uninhabited areas of the country, they would still be immigrants even if they lived where no one else was living. Or if they simply killed off all the townspeople and claimed the town, they would still be immigrants. Whther they conquered the locals, or simply moved to where no one was living didn't make the first Europeans any less
immigrants' as you apparently believe. If no one owned Manhattan, why did Europeans need to pay for it?????