Iona Abbey in the context of "Isle of Mull"

Columba (/kəˈlʌmbəˌ ˈkɒlʌmbə/) or Colmcille (7 December 521 – 9 June 597 AD) was an Irish abbot and missionary evangelist credited with spreading Christianity in what is today Scotland at the start of the Hiberno-Scottish mission. He founded the important abbey on Iona, which became a dominant religious and political institution in the region for centuries. He is the patron saint of Derry. He was highly regarded by both the Gaels of Dál Riata and the Picts, and is remembered today as a Catholic saint and one of the Twelve Apostles of Ireland.

Columba studied under some of Ireland's most prominent church figures and founded several monasteries in the country. Around 563 AD he and his twelve companions crossed to Dunaverty near Southend, Argyll, in Kintyre before settling in Iona in Scotland, then part of the Ulster kingdom of Dál Riata, where they founded a new abbey as a base for spreading Christianity among the pagan Northern Pictish kingdoms. He remained active in Irish politics, though he spent most of the remainder of his life in Scotland. Three surviving early-medieval Latin hymns are attributed to him.

The Catholic Church in Scotland, overseen by the Scottish Bishops' Conference, is part of the worldwide Catholic Church headed by the Pope. Christianity first arrived in Roman Britain and was strengthened by the conversion of the Picts through both the Hiberno-Scottish mission and Iona Abbey. After being firmly established in Scotland for nearly a millennium and contributing enormously to Scottish literature and culture, the Catholic Church was outlawed by the Scottish Reformation Parliament in 1560. Multiple uprisings in the interim failed to reestablish Catholicism or to legalise its existence. Even today, the Papal Jurisdiction Act 1560, while no longer enforced, still remains on the books.

Throughout the nearly three centuries of religious persecution and disenfranchisement between 1560 and 1829, many students for the priesthood went abroad to study while others remained in Scotland and, in what is now termed underground education, attended illegal seminaries. An early seminary upon Eilean Bàn in Loch Morar was moved during the Jacobite rising of 1715 and reopened as Scalan seminary in Glenlivet. After multiple arson attacks by government troops, Scalan was rebuilt in the 1760s by Bishop John Geddes, who later became Vicar Apostolic of the Lowland District, a close friend of national poet Robert Burns, and a well-known figure in the Edinburgh intelligentsia during the Scottish Enlightenment.

Iona (/aɪˈoʊnə/; Scottish Gaelic: Ì Chaluim Chille [ˈiː ˈxal̪ˠɪm ˈçiʎə] , sometimes simply Ì) is an island in the Inner Hebrides, off the Ross of Mull on the western coast of Scotland. It is mainly known for Iona Abbey, though there are other buildings on the island. Iona Abbey was a centre of Gaelic monasticism for three centuries and is today known for its relative tranquility and natural environment. It is a tourist destination and a place for spiritual retreats. Its modern Scottish Gaelic name means "Iona of (Saint) Columba" (formerly anglicised as "Icolmkill").

Iona's resident population is about 180. In March 1980, the Hugh Fraser Foundation donated much of the main island (and its off-lying islands) to the current owner, the National Trust for Scotland. The abbey and some church buildings are owned by the Iona Cathedral Trust.

Dál Riata or Dál Riada (also Dalriada) (/dælˈriːədə/) was a Gaelic kingdom that encompassed the western seaboard of Scotland and north-eastern Ireland, on each side of the North Channel. At its height in the 6th and 7th centuries, it covered what is now Argyll ("Coast of the Gaels") in Scotland and part of County Antrim in Northern Ireland. After a period of expansion, Dál Riata eventually became associated with the Gaelic Kingdom of Alba.

In Argyll, it consisted of four main kindreds or tribes, each with their own chief: the Cenél nGabráin (based in Kintyre), the Cenél nÓengusa (based on Islay), the Cenél Loairn (who gave their name to the district of Lorn) and the Cenél Comgaill (who gave their name to Cowal). The hillfort of Dunadd is believed to have been its capital. Other royal forts included Dunollie, Dunaverty and Dunseverick. Within Dál Riata was the important monastery of Iona, which played a key role in the spread of Celtic Christianity throughout northern Britain, and in the development of insular art. Iona was a centre of learning and produced many important manuscripts. Dál Riata had a strong seafaring culture and a large naval fleet.

Adomnán or Adamnán of Iona (Old Irish: [ˈaðəβ̃ˌnaːn]; Latin: Adamnanus, Adomnanus; c. 624 – 704), also known as Eunan (/ˈjuːnən/ YOO-nən; from Naomh Adhamhnán), was an abbot of Iona Abbey (r. 679–704), hagiographer, statesman, canon jurist, and saint. He was the author of the Life of Columba (Latin: Vita Columbae), probably written between 697 and 700. This biography is by far the most important surviving work written in early-medieval Scotland, and is a vital source for our knowledge of the Picts, and an insight into the life of Iona and the early-medieval Gaelic monk.

Adomnán promulgated the Law of Adomnán or "Law of Innocents" (Latin: Lex Innocentium). He also wrote the treatise De Locis Sanctis ('On Holy Places'), an account of the great Christian holy places and centres of pilgrimage. Adomnán got much of his information from a Frankish bishop called Arculf, who had personally visited Egypt, Rome, Constantinople and the Holy Land, and visited Iona afterwards.

Kenneth MacAlpin (Medieval Gaelic: Cináed mac Ailpin; Scottish Gaelic: Coinneach mac Ailpein; 810 – 13 February 858) or Kenneth I was King of Dál Riada (841–850), and King of the Picts (848–858), of likely Gaelic origin. According to the traditional account, he inherited the throne of Dál Riada from his father Alpín mac Echdach, founder of the Alpínid dynasty. Kenneth I conquered the kingdom of the Picts in 843–850 and began a campaign to seize all of Scotland and assimilate the Picts, for which he was posthumously nicknamed An Ferbasach ("The Conqueror"). He fought the Britons of the Kingdom of Strathclyde and the invading Vikings from Scandinavia. Forteviot became the capital of his kingdom and Kenneth relocated relics, including the Stone of Scone from the abandoned abbey on Iona, to his new domain.

Kenneth I is traditionally considered the founder of Scotland, which was then known as Alba in Gaelic, although like his immediate successors, he bore the title of King of the Picts. It was Donald II that first bore the title of King of Alba as recorded by the Annals of Ulster and the Chronicon Scotorum. One chronicle calls Kenneth the first Scottish lawgiver but there is no information about the laws he passed.

The Life of Columba (Latin: Vita Columbae) is a hagiography recounting the life of Columba, the founder of Iona Abbey, written a century after Columba's death by Adomnán, one of his successors as Abbot of Iona.

Adomnán (also known as Eunan), served as the ninth Abbot of Iona until his death in 704. James Earle Fraser asserts that Adomnán drew extensively from an existing body of accounts regarding the life of Columba, including a Latin collection entitled De uirtutibus sancti Columbae, composed c. 640 A.D. This earlier work is attributed to Cummene Find, who became the abbot of Iona and served as the leader of the monastic island community from 656 until his death in 668 or 669 A.D.

The Cáin Adomnáin (Old Irish pronunciation: [ˈkaːnʲ ˈaðəβ̃ˌnaːnʲ], KAWN AH-thuv-nawn, "Law of Adomnán"), also known as the Lex Innocentium (Law of Innocents), was promulgated amongst a gathering of Gaelic and Pictish notables at the Synod of Birr in 697. It is named after its initiator Adomnán of Iona, ninth Abbot of Iona after St. Columba. It is called the "Geneva Accords" of the ancient Irish and Europe's first human rights treaty, for its protection of women and non-combatants, extending the Law of Patrick, which protected monks, to civilians. The legal symposium at the Synod of Birr was prompted when Adomnáin had an Aisling dream vision wherein his mother excoriated him for not protecting the women and children of Ireland.