Folklore’s age of innocence, heralded by the conclusion of an extended period of centenaries, including those of the state, the Folklore of Ireland Society (2027), and the Irish Folklore Commission (2035), is coming to an end. A retrospect of the keywords and worlds of Irish folklore, béaloideas in Irish, is timely and, given their far-reaching ramifications, crucial. This book moves from English to Irish, zero folklore to folklore, Anglophone Irish folklore to béaloideas, back to no folklore again. The lead up to the relatively shallow revolutionary period following the invention of the term is counterbalanced with examples from the deeper time of ancestral inventiveness. While written in English the keynote is that the Irish language life-world, in one way or another, is its main burden or gravitas. There is no avoiding the fact, attested by the monumental archive of the historical commission, that the language of much of the lore and the lore of much of the language are prejudicially partitioned. This is the starting point of a genealogy traced through a remarkable series of chronological coincidences and clashes, in and out of lexicology, etymology, antiquarianism, history, folklore, ethnology, and anthropology, in short the science of life writ large. Ireland is a Gaelic Galápagos, there are few places in the world where the manifold roots of the scientific and cultural revolution go deeper. It epitomizes coloniality worldwide but its exemplarity is sunk deep in a collusive decolonialism aligned with manifest history. From the stone age to the phone age a protohistoric cant for framing the long concatenation of invasive manoeuvres on the island was curated in layers of chronology and chronicle that reached a crescendo in the nineteenth century. By the dawn of the twentieth it was charismatically ignited as a re-enlightenment or rebirth. To begin to separate wheat from chaff imagine three things, first the Hibernophone seanchas of the autochthonous life-world, second Anglophone Irish antiquarianism, folklore, and anthropology, and third béaloideas, often, though by no means always, Anglophone Irish folklore Gaelicized, quasi-learned or otherwise. This book is essential reading for anyone at all interested in Ireland.