The memorable images here are not those of victory and celebration, and the poem does not provide much regarding the feelings of the victors. Instead, the victory is defined by the extent of the waste and devastation, like at the end of action movies when no one has anything to say and no real perspective. "They left behind them to share the corpses / the dark-coated swarthy raven, / horn-beaked, and the gray-coated / eagle, white-tailed, to possess the carrion, / the greedy war-hawk and that gray wild beast, / the wolf in the forest" (60-65). These are the battlefield scavengers who appear repeatedly in early English poetry.
http://public.wsu.edu/~delahoyd/medieval/brunanburg.html
from the Dark Ages, probably as old as warfare, but in this case animals/birds, etc.