The main religion in the Republic of Ireland is Christianity which has historically been dominated by the Roman Catholic Church. The first religious beliefs and practices of ancient Ireland centred around Celtic tribes which was known as Celtic paganism. The Celtic pagans believed that spirits existed in natural objects such as trees and rocks. Such Celtic beliefs were held throughout different Celtic lands including Ireland, Britain and Gaul. Celtic pagan beliefs declined in the Roman Empire after the emperor Claudius outlawed Druidism in 54 BC. Celtic paganism gradually disappeared over the 5th and 6th centuries.
Today approximately 87% of Irish people living in the Republic of Ireland identify themselves as Roman Catholic. The second largest religious group is that of the Church of Ireland (Anglican) with approximately 3% of the population. Other religious groups include Muslim 0.8%, Christian (unspecified) 0.7%, Presbyterian 0.6% and those that describe themselves has having ‘no religion’ at approximately 6%.