Comment by yeahforsureman

Well yeah, there definitely was the period and cultural phenomenon called the Nordic Bronze Age, which also seems to closely match the dating of those rock carvings. You can read more about it elsewhere, but we're talking about relative largesse, reach and cultural interaction easily matching or exceeding that of the Vikings, originating and spanning a large part of the Indo-European sphere of dominance from Scandinavia to Mycenaean Greece and even beyond. Making and accumulating bronze itself drove the development of trade networks and connections of pretty extreme reach and complexity, unmatched for a long time after the Bronze Age Collapse.