What is "einar"

Einar is a given name deriving from the Old Norse name Einarr, which according to Guðbrandur Vigfússon is directly connected with the concept of the einherjar, undead warriors from Norse mythology. Vigfússon comments that 'the name Einarr is properly = einheri" and points to a relation to the term with the Old Norse common nouns einarðr (meaning "bold") and einörð (meaning "valour") .