St. Eunan (in Gaelic, Adhamhnán) was born in Donegal around 624 and educated by Columban monks. In 650, he moved to the island of Iona as a novice. In 679, he became the abbot. He returned to Ireland multiple times, keeping an open line of communication between Ireland and Scotland. He adopted the Roman dating of Easter (which caused some controversy within the Iona community) and argued for it in Ireland.
In 697, he wrote the “Law of Adomnan,” a set of laws designed to guarantee the immunity of various non-combatants in warfare. It is also called the “Law of Innocents.” Eunan also worked with the king of Northumbria for the release of 60 men who had been captured in raids.