Pre-Gaelic? But the jet black hair comes from the whole Mil of Spain (northern Spain eg Basque country) thing, not the earlier inhabitants.
But you live in Cornwall... they are a P-Celtic people, same as Scottish Picts and Ulster Cruithin, and it is well known that their characteristics are the lighter hair and larger build as described by Tacitus.
It is just common sense that the Goidils/Gaels should have darker hair, since they come from the same Q-Celtic language group as the Celtiberians.
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