Celtic Christianity or Insular Christianity refers broadly to certain features of Christianity
that were practiced across the Celtic-speaking world during the Early Middle Ages.
Some historians have described a distinct Celtic Church, embodying Chalcedonian Christianity, that
united the Celtic peoples and distinguished them from what would become the Roman
Catholic Church after the Great Schism. Other historians classify it as merely a set of
distinctive religious 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 Britain or Ireland, but which are not known to have spread
beyond a particular region. The term therefore denotes regional practices among the insular
churches and their associates, rather than actual theological differences.
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.
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
In German, the term "Iroschottisch" is used, with Lutz von Padberg placing the
same caveat about a supposed dichotomy between Irish-Scottish and Roman Christianity.
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 Saint Patrick, later others spread from Ireland to Britain with the Irish
missions 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).
Later interest in the subject has led to a series of "Celtic
Christian revival" movements, which have shaped popular perceptions of the Celts and their