Tablut is an obvious close relative to Hnefetafl, and an example of this game was collected by Carolus Linnaeus while in Samiland in 1732, and may very well be a survivor from the Viking Age. in the Sami version of this game, they say that the King's forces are representative of the Swedish army trying to escape from a Muscovite entrapment.
The rules to Tablut goes as such:
1) The pieces are arranged on the board as shown. The King's forces moves first, thereafter, the player make alternate moves.
2) Any piece may move any number of vacant spaces in a straight line or thagonally.
3) A piece is captured if two of the opposing pieces are moved onto adjacent spaces on either side of it. That piece is then removed from the board.
4) A piece may move unharmed onto an empty space between two opposing pieces
5) For the King to be captured, he must be surrounded by opposing pieces on all four adjacent spaces, or by three opposing pieces and the throne (the center space).
6) The King's forces wins if the King reaches the edge of the board, and loses if the King is captured.
7) When the King has a clear path to the edge of the board, the player must warn is opponent of that fact. If there are two of more clear paths to the edge, the King's player may safely claim victory.
Variations to the rules goes as such:
1) The throne may only be occupied by the King, but other pieces may pass over it freely.
2) The only way the King may win it to reach one of the four corners of the board.
3) Pieces may also be captured if trapped on both sides in the corners.