There have been interesting speculations from time to time about relict populations of neanderthals lingering on much longer in isolated and mountainous regions, especially in northern latitudes. The speculations often point to the very ancient folktales found in so many places and across cultures about cave dwellers, trolls and giants.
It’s now thought that woolly mammoths survived on Wrangel Island until about 4,300 hundred years ago. That’s the Bronze Age. Achilles might have lived longer had he chosen to hunt woolly mammoths rather than Trojans. Unless the last surviving ogres and trolls got him first.
Anyhow, it’s not hard to speculate on a foundation for the ubiquitous myths and legends. Michael Crichton did a novel on it, and I imagine others have as well. A few movies have picked it up. To what vanishing tribe did Grendel and Grendel’s mother belong before Beowulf extinguished the last of the line?
I guess we all retain something like 2% Neanderthal DNA but the Basque people have a higher percentage.
Also, Basque language and blood type are unique to them. It was suggested that there is a closer connection to what could have been Neanderthal language and DNA than what the rest of Europeans have.