IT says much about the state of the historical records of Scotland in the Middle Ages that we know so little about the important events of the 14th century in particular.

It is often said that there are more original documents and records about Scotland in that period in the UK, French and Vatican archives than there are in the archives of Scotland, and that would not be surprising given the damage done to Scotland’s historical collections by King Edward Longshanks, the Protestant Reformers and Oliver Cromwell, to name but the worst of the depredators. The proof of that assertion will be seen later in this column when we look at how the Vatican came up trumps in a centuries-old dispute over the legitimacy of a Scottish king.

The history of Glasgow from its foundation to the 15th century continues to be a combination of slight evidence, usually gathered from church and royal records, and guesswork from archaeology and other often flimsy sources. So it is not surprising that we know so little for definite about Bishop William Rae, the man credited with the transformation of Glasgow by the construction of the first stone bridge over the River Clyde.

I must emphasise straight away that Rae’s building of the bridge was a matter of dispute among historians of yesteryear, some pointing out that Glasgow in the mid-14th century could not have afforded such a bridge, while others hold that Rae had the assistance of local nobility in his endeavour.

Rae was a cleric in Glasgow, probably holding the office of precentor, the leader of worship, when he was elected bishop of the diocese by his fellow clerics in 1338. Church records show that he was consecrated in Avignon, then the papal residence, in 1339 on the orders of Pope Benedict XII.

Other church records show him sending the diocese’s contributions to the same Pope in 1342. He would go on to rule over the diocese until his death in January 1367, a period of nearly 29 years which was an exceptionally long time in a period where life expectancy was so much shorter than nowadays.

Sadly, we know for certain very little else about a man who was at the centre of events in Scotland and Glasgow at a time when the nation of Scotland was still unsure of its continued existence as a separate independent country.

Edward Balliol, for instance, did not give up his claim to the throne so balefully occupied by his father until 1356, when he accepted a pension from England’s King Edward III who needed peace with Scotland so he could make war on France.

As Bishop of Glasgow, Rae had a role in advising the king, David II, who came home from exile in France in 1341 at the age of 17. David proved to be a headstrong youth and got himself wounded and captured by the English when he invaded County Durham in 1346 and lost the Battle of Neville’s Cross in 1346.

It would be more than 11 years before David was released by King Edward III in return for a ransom that was never fully paid, though records showed that Bishop Rae and the Glasgow diocese paid their share for at least a few years.

Rae certainly played a decisive role in the succession to David. Robert Stewart had contracted marriage with his lover and the mother of his children, Elizabeth Mure (Mor), in order to legitimise their children so that he could be named as heir to King David and that his sons would also succeed to the throne.

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Bishop Rae intervened, working with fellow bishops and the royalty of Scotland and France to persuade the Pope to allow the marriage.

The petition he drew up stated: “The kings of France and Scotland, bishops William of St Andrews, William of Glasgow, William of Aberdeen, Richard of Dunkeld, Martin of Argyle, Adam of Brechin, and Maurice of Dunblane. Signification that although Elizabeth Mor and Isabella Boutellier, noble damsels of the diocese of Glasgow, are related in the third and fourth degrees of kindred, Robert Steward of Scotland, lord of Stragrifis, in the diocese of Glasgow, the king’s nephew, carnally knew first Isabella, and afterwards, in ignorance of their kindred, Elizabeth, who was herself related to Robert in the fourth degree of kindred, living with her for some time and having many children of both sexes by her; the above king and bishops therefore pray the pope that for the sake of the

said offspring, who are fair to behold (aspectibus gratiose), to grant a dispensation to Robert

and Elizabeth to intermarry, and to declare their offspring legitimate.”

The Pope granted Bishop Rae the right to legitimise the marriage – our own Queen is a direct descendant of King Robert II who unsurprisingly gave great favour to Rae and Glasgow thereafter – and in return, among other things, he founded a chaplaincy within the cathedral and paid for its upkeep.

Rae also played a role in the legitimisation of King Robert III, but it was not until the late 1600s that the documentation was found in the archives of the then Scots College in Paris, as copied to the Vatican archives, proving that both king Roberts were legitimate, thanks to Rae’s intervention. That was important as anti-Stewart factions had long questioned the legitimacy of the line.

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Yet did Rae build the Old Bridge of Glasgow? The traditional version of events is that he paid for seven arches of the magnificent stone bridge over the Clyde in roughly the same location of what is now Victoria Bridge – indeed, when the latter bridge was being built in the 19th century, the original well-preserved oak foundations of the Old Bridge were found.

The bridge may also have had the input of money from nobility but the theory that the cash was paid by a Lady Lochaw has long since been disproved.

Glasgow now had a bridge and indeed a Bridge Gate, the Briggait, and a town that had been rising almost exclusively on the north side of the Clyde was now able to expand southwards towards the existing – and often more important burghs – of Rutherglen and Govan.