The Barbarian Settlements are located south-west of Svargrond. There are three settlements, named after the major clans of raiders: Ragnir (located in an inactive volcano), Bittermor (located under the glacier) and Krimhorn (located on a peninsula).
You can travel to these fields talking with Buddel, asking for passage, then raider camp and confirm the answer. There is a chance he will take you to a different island, but the chances are lower after a patch. You can also reach the settlements by walking through the glacier and a small bridge to the west of Svargrond - it is a faster and cheaper way of getting there.
These settlements are profitable when you're talking about Loot. Barbarians drop lots of addon items and you can get some Tusks, Bear Paws and Furry Clubs when you're trying to avoid Mammoths and Polar Bears.
Bordering these 3 settlements, the glacier Formorgar hosts countless animals like Mammoths and Polar Bears and dangerous and fierce creatures such as Ice Golems and Crystal Spiders. Deep under the glacier, a strange cult has set up their camp in an old mine. It is rumoured that they are melting ancient demons there, hoping to be able to conjure a mighty archdemon one day.