The Celtic Mysteries was envisioned by William Butler Yeats as a potential occult society for Ireland; the purpose of it being the revitalisation of Celtic culture in a land dominated by foreign paradigms. The Order of Celtic Mysteries was going to bring the ancient traditions of the druids back to the people. Yeats recognised, however, that the true system the druids once practiced was severely degraded over time. Like the Hebrew tradition of the Qabalah, the Druidic tradition was also one that had its teachings given from mouth to ear, teacher to student, adept to initiate. Yeats decided that a revived system of magic should be based upon the modern magical tradition, though based upon the ancient secrets. For this reason he determined that the Order of Celtic Mysteries should be based upon the tradition of The Hermetic Order of the Golden Dawn. The Golden Dawn is considered the convergence of the various ancient traditions since the times of India and Mesopotamia. therefore, Yeats concluded that such an evolved system as the Golden Dawn would be a proper vessel for the Celtic Mysteries to be brought forth in. The necessity Yeats saw in the correspondence of the Irish tradition to the Golden Dawn structure of magic was that Irish spirituality would one day transform the world and act as the key of our true potentials.

The beginning of Yeats' work was to begin practical occult application of Irish mythology to the esoteric techniques that he learned in the Golden Dawn.