Possible Clues:

• Odin's worshippers
• Like Odin or 9-Down
• Language that gave us 'berserk'
• Like the deities Loki and Freya
• Icelandic settlers
• Visitors to Vinland
• From Trondheim, e.g.
• Old form of Norwegian
• Sixteen or seventeen Vikings captured here
• Stupid reason to lose one's tongue