It's unknown what Hereward did after obtaining the wand. He ultimately lost possession of the Elder Wand at some point, presumably by being defeated in a duel, killed, or disarmed.
The name "Hereward" is derived from the Old English elements here "army" and weard "guard", from which the magial kind of "ward" (as a protection) is also derived. This was the name of an 11th-century Anglo-Saxon leader who rebelled against Norman rule.
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