einherjar
The warriors who died fighting bravely and were brought by valkyries to Valhalla, where they feast and prepare for Ragnarok.
"We're the chosen of Odin, soldiers in his eternal army. The word einherjar is usually translated as lone warriors, but that doesn't really capture the meaning. It's more like...the once warriors—the warriors that fought bravely in the last life and will fight bravely again on the Day of Doom. Duck."
Where it comes from
From Old Norse einherjar (plural, literally “lone fighters”) (rarely attested singular einheri).
Adapted from the Wiktionary entry einherjar (CC BY-SA 4.0).