The Tuatha de Danaan: A Rowan Tree
pre-12th century—present. Old Irish | Modern Irish, folklore.
A giant with only one eye had agreed to guard the tree, provided he was allowed to eat its berries.
The men of Fionn mac Cumhaill’s warrior clan had a hurling match once against the former rulers of Ireland, the Sidhe – those ancient inhabitants who now lived in all the burial mounds and passage graves and hills of Ireland. The hurling match was abandoned after a while since neither side could score against the other, and when they all went away, the men of the Sidhe accidentally dropped a rowan berry from the bundle of food they were carrying. It grew into a tree with magic properties, one of which was that anyone who ate the berries from this tree,
any old person of a hundred years that would eat them would go back to be young again.
The people of the Sidhe who had lost the berry, found out who had dropped it and sent him off to find someone powerful enough to guard the tree for them. This musician of theirs – for he was the one who had dropped the berry – went off and over the sea to Lochlann, which is sometimes Norway in these stories and sometimes a mythical Otherworld across the broad ocean. There he found
a very big man who agreed to guard the tree provided that he was allowed to eat its berries. He was ugly with crooked teeth
and one eye only in the middle of his forehead. Like the cyclops Polyphemus.