Einherjar

In Norse religion the einherjar or einheriar were spirits of warriors who had died bravely in battle. The name is Old Norse for "one-army-ers". It is often interpreted as "outstanding fighter", but might also signify "those who are all [now] in one army", because when alive on earth they were in many armies and bands, but now they are all in the Army of the Dead.
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[Norse] The Einherjar are the heroes who have died with great bravery on the battle fields. These heroes are prepared in Valhalla for the oncoming battle of Ragnarok. In the morning they are woken by the crowing of the cock Gullinkambi ("golden comb"). During the day they train and fight, until they cut each other to pieces. At night they feast at Odin's side and their wounds are miraculously healed. On the day of Ragnarok, the bravest of the Einherjar will march with Odin to battle the frost giants, the enemies of the gods.