The Celtic artistic tradition of interlace is not limited to just knots and braids. Fantastic animals with limbs, bodies, tongues and tails looped and tangled together, are a great part of the tradition. The term zoomorphic art refers to the animal interlace motif.
The great Celtic gospel manuscripts of the early medieval period are often decorated with beasts and birds, many of which are not easily recognized species. The imagination and beauty expressed in the illuminated pages of the Book of Kells, the Book of Durrow and the Lindisfarne Gospels, all contain zoomorphic designs, that dazzle and inspire thirteen hundred years after their creation. Much of the metalwork and jewelry of the same period is also adorned with interlaced birds and beasts.
The symbolism of animals in medieval art can be partially understood through books called the Bestiaries, which were encyclopedias of animals and the supposed natural history and spiritual lessons that the various species represented. Not only did these books contain descriptions of common domestic animals and local wild creatures that medieval Europeans would be familiar with, but also included exotic animals like elephants and lions that most readers would never encounter.
Additionally mythical creatures like the salamander that lives in the fire, griffins, unicorns and other imaginary beasts were described. These were believed to be just as real as the species of faraway lands. The attributes of familiar animals like dogs, cats and horses were very plausible and did not contradict the observations that people would normally experience. The exotic and imaginary species were endowed with amazing qualities and habits, which were taken on faith as these animals were not often encountered. The Bestiaries were based on an anonymous of 2nd century Greek work called Physiologus. In medieval times Bestiary books were second only to the Bible in their circulation.
The most common creatures to be represented in medieval Celtic art are quadrupeds, birds and serpents. Of the quadrupeds, the most common are dogs and lions, although it can be difficult to tell them apart due to their highly abstract style. The symbolic attributes of a dog is his loyalty and esteem for his master. A dog finds the truth through his superior perception and the tongue of a dog has healing. Lions are proud and strong, symbolic of royalty. A lion sleeps with his eyes open and is therefore ever vigilant. A lion does not get angry unless it is wounded.
Among birds, the most commonly represented in medieval times are eagles and peacocks. Eagles are the royalty of the bird kingdom. They are esteemed for their power and especially for the acute vision of their eyes. It is believed that when an eagle grows old and its vision becomes clouded, that it can fly so high as to be near enough the sun that the cloudiness is burned away and vision restored. Peacocks were believed to have flesh that would not decay after death and therefore symbolic of everlasting life. It is also quite likely that because a peacock is such a fancy bird, that artists given to extravagant representation would naturally be attracted to it.
Snakes and serpents lend themselves to interlaced Celtic art as the natural form of their slender bodies needs less abstraction to contort them into knots and spirals. Symbolically snakes may be either good or evil. The tempter of Eve was the Devil in the guise of a serpent, but as a snake sheds it’s skin and is renewed it is symbolic of spiritual renew and salvation.
Various ancient legends and native folk beliefs of the Celtic people supplement the symbolic vocabulary of zoomorphic designs. The story of Saint Columba and the Heron transforms that feathered friend from being a spooky messenger from the world of the dead, as it was regarded in pagan times, to being a more benign visitor from the unseen world, as well as being a symbol of exile. Stories like those of water kelpies, the Salmon of Knowledge and the Hound of Chullainn have made for continued use of zoomorphic abstractions down through the Celtic Revival of the 19th century to the Celtic Renaissance of the present.