The Céli Dé, who were also known as the Culdees, was a monastic order with settlements in Ireland and Scotland. Although Christian, the order preserved some Celtic customs and traditions.  Céli Dé means 'God's comrade' or 'sworn ally'.

It is believed they had a particular interest in the care of the poor and the sick. By the end of the thirteenth century, the Christian Church on the Continent had such an influence on the Church in Ireland that the Céli Dé's distinctiveness had diminished.