The Latin word for Ireland is Hibernia which derives from Iberia, the origin of the largest group of Celts who came from the Iberian Peninsula (Spain and Portugal). Those people were known as the Milesians and they came to Ireland roughly 2,000 years ago. Ireland was known as "Hibernia" for at least 1,000 years before the Spanish Armada came.

The Spanish Armada have absolutely nothing to do with the dark haired Irish.