The Ulfberht Sword also recognized as the Viking sword was a double edged sword used by the Vikings. The sword was carried by the top men in Viking society and was a weapon of status, it is mentioned as one of the most superior swords ever created and because of it's superior steelwork it held out as the most superior sword until the industrial revolution. The first Ulfberht sword to be found was in 850 AD. Demonstration of the power of the Ulfberht
The excellent documentary about this sword and its re-creation by a contemporary master swordsmith: By the way... righteous beard...