Celtic Christianity

Celtic Christianity or Insular Christianity refers broadly to certain features of Christianity that were common, or held to be common, across the Celtic-speaking world during the Early Middle Ages. "Celtic Christianity" has been conceived of with differing levels of specificity: some writers have thought of it as a distinct "Celtic Church" uniting the Celtic peoples and distinguishing them from the "Roman" Catholic Church, while others classify it as simply a set of distinctive practices occurring in those areas. Scholars now reject the former notion, but note that there were certain traditions and practices used in both the Irish and British churches but not in the wider Christian world. These include a distinctive system for determining the dating of Easter, a style of monastic tonsure, a unique system of penance, and the popularity of going into "exile for Christ". Additionally, there were other practices that developed in certain parts of the Celtic world, but which are not known to have spread beyond a particular region. Rituals associated with Celtic Christianity are now almost completely lost, though two books, the Bobbio and the Stowe Missals, contain the Irish Ordinary of a daily Mass in late, Romanized form.

The term "Celtic Church" is deprecated by many historians as it implies a unified and identifiable entity entirely separate from the mainstream of Western Christendom. Others prefer the term "Insular Christianity". As Patrick Wormald explained, “One of the common misconceptions is that there was a ‘Roman Church’ to which the ‘Celtic’ was nationally opposed.” Celtic-speaking areas were part of Latin Christendom as a whole at a time in which there was significant regional variation of liturgy and structure with a general collective veneration of the Bishop of Rome that was no less intense in Celtic areas.

Nonetheless, it is possible to talk about the development and spread of distinctive traditions, especially in the sixth and seventh centuries. Some elements may have been introduced to Ireland by the Briton St. Patrick, later others spread from Ireland to Britain with the Irish mission system of Saint Columba. The histories of the Irish, Welsh, Scots, Breton, Cornish, and Manx Churches diverge significantly after the eighth century (resulting in a great difference between even rival Irish traditions).