Fantastic item!
These are known as ‘Yetholm-type’ shields, after the Yetholm peat bog in southern Scotland which has yielded three examples. Twenty-two are known (some of which are fragmentary), including one from Denmark, and a further seven or eight mentioned in literature whose whereabouts are unknown. They’re sufficiently similar that they must have come from the same workshop, if not the same craftsman.
Doubt has been expressed over their use in combat since they have only small hand-holds around 110mm across, and they’re made of high-tin bronze which (although strong) is only about 0.6mm thick, but with a folded-over rim to give rigidity. There’s no evidence for them having been wood-backed, although one example showed signs of a leather backing which would have further stiffened it but not really strengthened it very much.
Suggestions of battle damage on this example have been undermined by the ceremonial nature of the burial of shields of this type, with one example found to have been stabbed three times with a wooden stake in what appears to have been a sacrificial ritual. There is however another example from Oxfordshire that has two lozenge-shaped perforations, interpreted as from a spearhead and several other piercings that had been hammered flat to close the gaps, suggesting that the shield might have experienced more than one combat event.