Celtic is a symbol that combines across with a ring surrounding the intersection; the cross’ stem being longer than the other threes’ intersection. It belongs to a wider group of crosses with a nimbus. The Celtic Christians combined the Christian cross with the nimbus to create high crosses – a free-standing cross made of stone which was often richly decorated. The Celtic Revival shape, usually decorated with interlace and other motifs from Insular art, became popular for funerary monuments and other uses, and has remained so, spreading well beyond Ireland.
In Galicia, a distinct form of cross similar to the Insular Celtic shapes is found, often topping horreos (granaries) as a protective measure against any kind of evil. They can also be found atop churches and in cemeteries since the beginning of the 20th century. Insular Celtic shapes are unusual in cruceiros (high crosses), a very characteristic Galician style that combines a Celtic cross with a Celtic simple knot.
The Celtic Revival of the mid-19th century led to an increased use and creation of Celtic crosses in Ireland. In 1853, casts of several historical high crosses were exhibited at the Dublin Industrial Exhibition. In 1857, Henry O’Neill published Illustrations of the Most Interesting of the Sculptured Crosses of Ancient Ireland. These two events stimulated interest in the Celtic cross as a symbol for a renewed sense of heritage within Ireland.
New versions of the high cross were designed for fashionable cemetery monuments in Victorian Dublin in the 1860s. From Dublin, the revival spread to the rest of the country and beyond. Since the Celtic Revival, the ringed cross became an emblem of Celtic identity, in addition to its more traditional religious symbolism.
Modern interest in the symbol increased because of Alexander and Euphemia Ritchie. The two worked on the Isle of Iona in Scotland from 1899 to 1940 and popularized use of the Celtic cross in jewelry. Using the celtic cross in fashion is still popular today.
Since its revival in the 1850s, the Celtic cross has been used extensively as grave markers. Straying from medieval usage, when the symbol was typically used for a public monument. The Celtic cross now appears in various retail items. Both the Gaelic Athletic Association and the Northern Ireland national football team have used versions of the Celtic cross in their logos and advertising.