Celtic Concho, 22 x 22 mm, Antique brass plated, 1 rivet pin
Celtic knots are a variety of (mostly endless) knots and stylized graphical representations of knots used for decoration, adopted by the ancient Celts. These knots are most known for their adaptation for use in the ornamentation of Christian monuments and manuscripts like the 8th century St. Teilo Gospels, the Book of Kells and the Lindisfarne Gospels. The use of interlace patterns had its origins in the art work of the late Roman empire. Knot patterns first appeared in the third and fourth centuries AD, and can be seen in Roman floor mosaics of that time. Interesting developments in the artistic use of interlaced knot patterns are found in Byzantine architecture and book illumination, Coptic art, Celtic art, Islamic art, Medieval Russian book illumination, Ethiopian art, and European architecture and book illumination. Spirals, step patterns, and key patterns are dominant motifs in Celtic art prior to the Christian influence on the Celts, which began around 450 A.D. These designs found their way into early Christian manuscripts and art work with the addition of depictions from life, such as animals, plants and even humans. In the beginning the patterns were intricate interwoven cords, called plaits, which can also be found in other areas of Europe, like Italy in 6th century. A fragment of a Gospel Book, now in the Durham Cathedral library and created in northern Britain in the 7th century, contains the earliest example of true knotted designs in the Celtic manner. Examples of plaitwork (a woven, unbroken cord design) predate knot work designs in several cultures around the world, but the broken and reconnected plaitwork that is characteristic of true knot work began in Northern Italy and Southern Gaul and spread to Ireland by the 7th century. The style is most commonly associated with the Celtic lands but it was also practiced extensively in England and was exported to Europe by Irish and Northumbrian monastic activities on the continent. In modern times Celtic Art is popularly thought of in terms of national identity and therefore specifically Irish, Scottish or Welsh. J. Romilly Allen has identified "eight elementary knots which form the basis of nearly all the interlaced patterns in Celtic decorative art; however, there is no evidence to indicate that a knot had any specific philosophical or religious significance beyond perhaps the most obvious, that being the intricacy capable in the work of humans, itself reflective of the intricacy of Natural forms. Many items decorated with knotwork have been found in archaeological sites.