It is unclear whether a form of Early Irish astrology existed prior to contact with Western astrology, as the earliest Irish language sources are simply translations from standard Western sources.
While the pre-Celtic megaliths in Ireland are often aligned with solar and lunar phenomena, no evidence has been found for the type of planetary symbol system as seen in other cultures' systems of astrology.
Writing about early Irish-language translations of Western astrology texts, Ellis speculated that there could have been an earlier, native Irish astrological system, even though there is no evidence for this, arguing that "a study of linguistic concepts and early cosmological motifs and calendrical philosophies of both Celtic (inclusive of Old Irish) and Sanskrit/Vedic cultures give a path back to the common Indo-European roots of our cultures". However, the symbolism and structure of the astrological system he referenced is not based in Irish symbolism, but in the standard Greco-Roman mythology-based symbolism used in Western astrology, just with the figures (Leo the Lion, etc.) given Irish names.