The history of St Mirin has grown dim and much of what is known about the saint is difficult to separate from fable. However, it is believed that Mirin was of noble birth. While still a young boy, his mother took him to the monastery of Bangor Abbey in County Down in the north east of Ireland, where he was placed under the care of St. Comgall. St Mirin later took oversight of the monastery and thus became the prior of Bangor Abbey, where he accepted visitors and sojourners. Later on, St Mirin travelled to the camp of the High King of Ireland with the purpose of spreading the Christian faith. Having heard of Mirin's arrival, the king refused to allow the saint to enter the camp. Mirin, thus slighted, was said to have prayed to God that the king might feel his wife's labour pangs, her time being near. The legend continues that, just as St Mirin had prayed, the king fell ill and roared in pain for three days and nights. In desperation the king sought out Mirin and granted him all he wished, including the right to go out and preach the Gospel to the men of his camp. In response to these concessions St Mirin prayed on his behalf and he was freed from his pain. Thereafter he was appointed to the west of Scotland and, after a long and difficult journey, arrived where the town of Paisley now stands. The area had recently been abandoned by the Romans and was in the possession of a powerful local chieftain. This chief took a liking to Mirin and the saint was allotted a small field near the river in the southern part of town. This plot was called St Mirin's Croft until it was later developed. He founded the first church in Paisley, thought to be at Seedhill and after his death the shrine of Saint Mirin became a centre of pilgrimage. In various charters and Papal Bulls Mirin is referred to as The glorious confessor, Saint Mirin. His image was engraved on the seal of the Abbey, depicting him in the vestments of a bishop. Around the seal was inscribed the prayer O Mirin, pray for your servants. In King James IV's Charter of 1488 raising Paisley to the status of burgh of barony, one of the reasons cited was "the singular respect we have for the glorious confessor, Saint Mirin".
Mirin in modern Scotland
There is a chapel within Paisley Abbey, dedicated to Mirin containing a sculptured stonefrieze depicting the life of the saint. The Roman Catholic St Mirin's Cathedral is also named in his honour. St Mirren F.C., a football club from Paisley, is named after him. The St Mirin Burn flows into the White Cart Water close to the town centre. He is also commemorated by St Mirren Street which links Paisley Cross to Causeyside Street. Since the closure of St Mirin's and St Margaret's High School in 2001, there has been no school in the town dedicated to the saint. However, there is a St Mirin's Primary School in the Simshill area of the neighbouring city ofGlasgow. Elsewhere in Scotland, the island of Inchmurrin in Loch Lomond and a farm called Knockmurran near Coylton in Ayrshire are named after him. St Mirin's Well can be found near Kilsyth in Stirlingshire.