IT was in this week of the year 563 that a hugely important development in the history of Scotland took place on the island of Iona.
On the date traditionally held to be May 12, 563, St Columba and 12 companions from Ireland arrived on Iona. At that time only the Kingdom of Dalriada in what is now Argyll and the very southern regions of what is now Dumfries and Galloway were Christian. By the time Columba died in 597, most of the Scottish mainland was Christian, and the Scots – descendants of immigrants from Ireland – and the Picts were united by religion in what historians call the Celtic Church.