Ireland is a country rich in history. It reached a Golden Age in the arts in the 7th and 8th centuries, after the collapse of the Roman world and before the rise of a new central authority in Europe under the Emperor Charlemagne.  Because Ireland is an island, it was protected during this period of upheaval, which allowed Ireland to experience growth after the Roman Empire declines. Some argue that the Irish saved western civilization, particularly in the writings and studies of the Irish monks, whose monasteries helped preserve  learning during this Golden Age. One marvelous product of this period is the famous Book of Kells (detail below, with link), a fabulously detailed  manuscript illumination, done entirely by hand with loving attention by Irish monks.
Perhaps Irish High Crosses are the most universally recognized objects from Ireland in the Middle Ages. These works in stone can reach 15 to 16 feet in height (see the Art History teacher standing next to the Tall Cross, County Louth, Ireland). Irish High Crosses are recognized by the circle that intersects the arms of the cross.  Like much of the decoration that fills the body of the cross, the circle is actually derived from pagan imagery.  The circle derives from the sun, a symbol of continuation, renewal and rebirth. By visiting the monastery where this cross is located, I was able to discover that ALL the crosses in the monastery faced east-west.  The image on the western face of the crosses was often a crucifixion scene; the image on the eastern face often was a resurrection scene.  This, too, relates to the sun as a symbol of rebirth and renewal.  In short, the very position of these crosses refers to pagan traditions, providing evidence that, in Ireland during the Middle Ages, there was an incredible blending of Christina and Pagan traditions.