The ancient Celtic peoples were a far-ranging ethnic group that made an impact on broad swathes of Europe centuries before the rise of Rome itself. Though very little is known for certain about these various Celtic tribes, the accounts of Roman authors of their neighbors to the north have made a major impact on the modern understanding of these fascinating peoples.

Among other elements of the ancient Celts that many people find fascinating is their astrological systems and the symbolism there is. Though the Roman and later Christian authors who documented the astrological knowledge of the ancient Celts was heavily wrapped up in their own cultural biases, a number of elements of Celtic astrology have emerged through the writings of a number of ancient authors. Among other elements that were important were animals according to Celtic astrology expert Angharad Reese.

Much like the zodiac systems that emerged in Roman and related civilizations, these zodiac signs were based on constellations (though it is also quite likely that some of the truly ancient Celtic understandings of the stars were lost in translations and the Roman and Christian authors of later eras simply tried to put Celtic understandings inside their own). Each zodiac sign was based on a single animal, which the ancient Celts considered as being the animal depicted by a specific constellation, be they a horse, a dragon or a butterfly. That said, each animal archetype did have its own meanings to the Celts, some of which were, again, not fully understood by those outsider authors who documented them, but enough details have emerged in their accounts to put together a fascinating picture of the astrological systems of Celtic bards and druids of the Iron Age Celtic societies.

A full list of these zodiac signs and the traits assigned to them would take quite a while to detail, but each of these animals were drawn from the observations of the Celts. Some of these animals, such as the white horse, the butterfly and the stag, were drawn from direct observation of these animals as the Iron Age astrologers assigned human traits to certain animals seen in the stars. Others, such as the green dragon and the sea serpent, were based on a more mythological perspective, though as with the animals the Celts observed, these creatures too were assigned human traits. Using a mix of both mundane and mystical animals, the Celts detailed a total of thirteen creatures in the stars.