GLASGOW Cathedral is one of Scotland’s most magnificent medieval buildings, and the only cathedral on the Scottish mainland to survive the Protestant Reformation almost intact.

The building dates mostly from the 1200s and parts of it are older still. It was dedicated to St Kentigern or St Mungo, who is credited with founding Glasgow, being its first bishop and of course, he is Glasgow’s patron saint. The Cathedral is reputedly built on the site of St Mungo’s original church, founded in the sixth century on the banks of the Molendinar Burn, and was constructed over the spot where he was buried in around 612.

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The impetus for building the Cathedral was the decision in c.1115 by David Prince of Cumbria (later King of Scotland) to reinstate the Diocese of Glasgow which made Glasgow an episcopal centre of an enormous diocese. The new cathedral at Glasgow was first consecrated in 1136 in the presence of King David I and his court.

It was reconsecrated in 1197 after a fire, when a new cathedral was built, of which a single vaulting shaft in the south aisle of the lower church is all that survives today. Bishop Jocelin was responsible for overseeing its reconstruction. He commissioned a monk, Jocelin of Furness, to write a biography of St Mungo to generate enthusiasm for Glasgow’s patron saint, which resulted in a partially completed choir, new nave, and transepts. The Cathedral was consecrated in July 1197.

Papal bulls in 1161 and 1211 required adult residents from the diocese to make annual pilgrimage to the shrine of St Mungo making Glasgow and its Cathedral a centre for pilgrims. In 1301 King Edward I of England worshipped at St Mungo’s shrine and tomb. Very unusually for a Cathedral, it was also the parish church for the town’s inhabitants.

The building was continually repaired and extended throughout medieval times. During the period of Bishop Glendinning (1387-1408) it was struck by lightning and its original wooden spire burned down. It was replaced with a stone version.

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In 1560 the Scottish Reformation saw Archbishop Beaton escape to Paris, taking the diocesan, city and university archives with him. All the Catholic furnishings such as altars and sculpture were removed, and the roof was apparently stripped of lead. In 1562 David Wemyss became the first Protestant minister of Glasgow Cathedral.

The fabric of the cathedral suffered from vandalism and plunder, and by 1574 it was in sufficiently bad condition to attract the attention of the Glasgow town council. The tradition is that Glasgow Trades House defended the cathedral from further damage, enabling it to survive the Reformation relatively unscathed.