The triple spiral occurs as a religious symbol in many early cultures. As far as the Atlantic Celts are concerned, it makes its appearance in around 3200 BC in the carvings on the megalithic tombs in the Boyne Valley in Ireland. The most famous example is the double-triple spiral carved into a stone right at the heart of the great megalithic passage grave ofNewgrange.
Each of the three spirals consists of two lines. The symbolism may be simple: one path in and the other out. With any labyrinth, there has to be a way in and a way out, and the spiral is the simplest form of labyrinth. The triple spirals at Newgrange date from the time of the passage grave’s construction, 5,000 years ago. So the triskele has been part of the Celtic culture of the Atlantic west for a very long time.
It is possible to manufacture all kinds of symbolism for the triple spiral. It was in use in ancient Greece. It was in use as an ancient symbol of Sicily. Pliny the Elder attributed the origin of the Sicilian triskele to the triangular shape of the island. This is possible, but it is an explanation that will not do elsewhere, for instance in Neolithic Ireland.
In the early Christian, post-Roman world, the device was easily adopted as a symbol of the Trinity. It must be suspected, though, that usually when it was used in illuminated Gospels in the eighth and ninth centuries AD it was for the convenience of its shape—a natural space-filler between the curves of the main designs and the comers of the page.
Celtic neo-pagans also use the triskele symbol to represent a range of triplisms. It is tailor-made to represent any of the many triads in the Celtic tradition (see Rule of Three).