Saint Iserninus (or ''Isernius'') () was an early
Christian
A Christian () is a person who follows or adheres to Christianity, a Monotheism, monotheistic Abrahamic religion based on the life and teachings of Jesus in Christianity, Jesus Christ. Christians form the largest religious community in the wo ...
missionary
A missionary is a member of a Religious denomination, religious group who is sent into an area in order to promote its faith or provide services to people, such as education, literacy, social justice, health care, and economic development.Thoma ...
of
Ireland
Ireland (, ; ; Ulster Scots dialect, Ulster-Scots: ) is an island in the North Atlantic Ocean, in Northwestern Europe. Geopolitically, the island is divided between the Republic of Ireland (officially Names of the Irish state, named Irelan ...
who is associated with
Saint Patrick
Saint Patrick (; or ; ) was a fifth-century Romano-British culture, Romano-British Christian missionary and Archbishop of Armagh, bishop in Gaelic Ireland, Ireland. Known as the "Apostle of Ireland", he is the primary patron saint of Irelan ...
and
Saint Auxilius in establishing
Christianity
Christianity is an Abrahamic monotheistic religion, which states that Jesus in Christianity, Jesus is the Son of God (Christianity), Son of God and Resurrection of Jesus, rose from the dead after his Crucifixion of Jesus, crucifixion, whose ...
in the south of that island. More recent research associates him not with Patrick but with
Palladius.
Traditional view
Saint Iserninus is thought to have been a
Briton
British people or Britons, also known colloquially as Brits, are the citizens of the United Kingdom, the British Overseas Territories, and the Crown dependencies.: British nationality law governs modern British citizenship and nationality, w ...
or
Irishman
The Irish ( or ''Na hÉireannaigh'') are an ethnic group and nation native to the island of Ireland, who share a common ancestry, history and culture. There have been humans in Ireland for about 33,000 years, and it has been continually inhab ...
, and is associated with the lands of the
Uí Cheinnselaig in
Leinster
Leinster ( ; or ) is one of the four provinces of Ireland, in the southeast of Ireland.
The modern province comprises the ancient Kingdoms of Meath, Leinster and Osraige, which existed during Gaelic Ireland. Following the 12th-century ...
. He was originally named ''Fith'', and he may have been ordained a
deacon
A deacon is a member of the diaconate, an office in Christian churches that is generally associated with service of some kind, but which varies among theological and denominational traditions.
Major Christian denominations, such as the Cathol ...
at
Auxerre
Auxerre ( , , Burgundian language (Oïl), Burgundian: ''Auchoirre'') is the capital (Prefectures in France, prefecture) of the Yonne Departments of France, department and the fourth-largest city in the Burgundy historical region southeast of Par ...
with Patrick and Auxilius.

Iserninus is referred to as a
bishop
A bishop is an ordained member of the clergy who is entrusted with a position of Episcopal polity, authority and oversight in a religious institution. In Christianity, bishops are normally responsible for the governance and administration of di ...
in the ''
Annals of Ulster
The ''Annals of Ulster'' () are annals of History of Ireland, medieval Ireland. The entries span the years from 431 AD to 1540 AD. The entries up to 1489 AD were compiled in the late 15th century by the scribe Ruaidhrí Ó Luin� ...
'', and he is recorded as having begun his mission in 439 AD. According to
Patrick F. Moran, St. Patrick assigned the valley of the Liffey to Auxilius and Iserninus.
Modern studies
According to historian
Charles Thomas, "The weight of current opinion is perhaps in favour of associating
Secundinus,
Auxilius, and Iserninus with Palladius rather than with Patrick."
A tradition at
Aghade,
County Carlow
County Carlow ( ; ) is a Counties of Ireland, county located in the Southern Region, Ireland, Southern Region of Ireland, within the Provinces of Ireland, province of Leinster. Carlow is the List of Irish counties by area, second smallest and t ...
, holds that Iserninus founded a church there and was later buried there. Iserninus is also called the founder of the church at
Old Kilcullen, where he was reputedly appointed as bishop by St. Patrick, possibly along with St. Mactail. Kilcullen began as a monastic settlement, in the period around 448. The choice of location for the settlement was perhaps related to the nearby
Dun Ailinne,
[Johnston, Susan; Wailes, Bernard (2007), ''Dún Ailinne: Excavations at an Irish Royal Site 1968–1975'', Philadelphia: University Museum Publications, ] a ceremonial site related to the kings of Leinster.
References
Sources
*Dumville, David N. "Auxilius, Iserninus, Secundinus and Benignus." In ''Saint Patrick, AD 493-1993'', ed. by David N. Dumville and Lesley Abrams. Studies in Celtic history 13. Woodbridge: Boydell, 1993. pp. 89–105. .
People from County Carlow
5th-century Irish bishops
Christian missionaries in Ireland
5th-century Christian saints
Medieval Irish saints
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