The Celtic Tribes were united by common speech, customs and practises each headed by a king and divided by class into priests, warrior nobles, and commoners. They regarded the Earth as the property of divine forces not of human kind, treating the land and all its creatures with respect and reverence - their shamanistic religion was known as Druidism. The Celts regarded their laws, genealogies and spiritual disciplines as sacred, and required them to be transmitted orally. Their priests spent years learning their lengthy sacred texts by heart to preserve and transmit knowledge.
At the height of their influence, between the 5th and 1st centuries BC, the Celtic tribes covered lands extending from what is now Spain all the way to the shores of the Black Sea. While retaining a distinct style of its own, the art and architecture of the Celts was nevertheless influenced by the people they encountered and conquered including the ancient Persians, Etruscans, Greeks, Romans and Scythians. On the whole Celtic art is still considered one of the greatest contributions made by any society to European art. The elaborate Rosslyn Chapel is an extraordinary example of the influence of Celtic art with its highly sophisticated and abstract knot work, elliptical curves, spirals, chevrons and labyrinthine patterns and, just as often, entwining plant and animal designs. The Celts were highly ritualistic and religious, their deities were tribal and their reverence for the natural world absolute. Each tribe or clan would have its own names for particular gods and goddesses, accounting for the over 300 different names recorded in Celtic mythology. As in all shamanistic traditions, animals guardians and guides chose you; you do not choose them. On a journey to the Otherworld the priest watched carefully for a creature to appear three or more times so they would know they, or the person they been 'travelling' for, had been accepted by that creature. Individuals often painted their shields, tattooed their body, or wore gold or bronze jewellery with images of their unique guardian.
There is some evidence that heraldry originates with Celtic animal guardians and the characteristic traits of the animals they represented.