The oldest poem in the Irish language?

This is my second poem in the language in the ancient druids of Ireland. This one was allegedly composed by Amairgen, one of the sons of Míl, mythological ancestors of the Gaels. Coming from Spain, Amairgin and his brothers defeated the ancient gods, the Túatha Dé Dannan, who already lived in Ireland. The poem is hauntingly beautiful in its simplicity and I'll not only teach you how to recite it, but I also explain the meaning of each word.