By Linda Root
In criminal prosecutions, dates are often significant, sometimes critical, and even dispositive of a case's outcome. When viewing the last year of the reign of Marie Stuart, Queen of Scots through the eyes of an experienced prosecutor, June 20, 1567 becomes a landmark date.
Placed in the chronology of events occurring in Scotland during that regime- shattering summer, the emergence of damning evidence against the queen five days after her surrender at Carberry Hill casts more doubt on the men who produced it than on the guilt or innocence of the queen whom they claimed had been complicit in her husband’s murder. The tribunal which investigated the charges against the queen was hardly impartial and her accusers were the true principals in the very crime of which she was charged. It all began on June 20 in the course of a most unlikely dinner attended by two men who openly disliked one another, each of whom probably ate with a table knife in one hand and a sgian dubh hidden in the other.
According to Morton, June 20, 1567 is the day that the infamous 'Casket Letters' were dropped into his lap, a most fortuitous windfall for the prosecution's case, although the evidence alleged to have surfaced on that important day was not presented to the Scottish Parliament when it indicted the queen the following December, never presented in its original form to the tribunal that heard the case against her at York and Westminster in 1568, and early in the independent reign of her son and successor James VI the evidence mysteriously disappeared. Of utmost importance, while discovery of the evidence was leaked to Cecil and the French via hint and innuendo, the actual evidence was not disclosed while the queen was still in Scotland and public sentiment was so critical to the Regent's cause, and it was never shown to the queen.
Morton was Marie Stuart's bitter enemy, the man who orchestrated the murder of her friend and confidante David Rizzio so that it occurred in the heavily pregnant queen’s presence, and who was instrumental in changing the terms of her surrender at Carberry from house arrest at Holyrood to close confinement in the dismal island fortress at Loch Leven.
On June 20, five days after the knight Sir William Kirkcaldy delivered the queen into his clutches, Morton and Maitland were settled in for a supposedly friendly dinner when they were interrupted with astonishing news.
There had been an incursion into Edinburgh Castle by a trio of men aligned with the queen's third husband, her-co suspect Bothwell, and one of them, James Dalgleish, had been discovered with evidence in his possession. At least that was the story Morton brokered to the English sixteen months later when the queen's brother, the Scottish Regent Moray placed Morton’s sworn declaration in evidence before the assembled tribunal at York. It is what happened in the intervening month that makes Morton's averments suspicious.
Kikcaldy at Carberry by Russ Root
There are several different views as to how this most unlikely discovery surfaced and whether Morton's words are credible.
The first red flag is the dinner itself, because Morton and Maitland were not friends. What bound them together, if anything was the fact that each had the goods on the other. But since the two of them were running Scotland until the queen's half-brother Moray returned from wherever he had gone to stay clear of the fracas that followed his sister's marriage to Bothwell, I concede that perhaps they did have matters to discuss. Moray was due to return in a matter of days, and Morton and Maitland needed to have their ducks lined up.
At that point, while the surrender of the queen had been accepted by the common folk, who had been shocked by her behavior with Bothwell, there were already grumblings coming from the Knight Kirkcaldy of Grange, who had procured the queen's surrender on very specific terms and was of the opinion that her harsh treatment left his honor tarnished. Kirkcaldy had served in France with King Henri Valois in a setting where chivalry was the watchword and a man's honor was everything.
The entire campaign the lairds had waged had been launched on the premise that they were merely attempting to free their befuddled queen from Bothwell's thrall. With Bothwell in flight and essentially neutralized, there was no good reason for the queen to be locked up at Loch Leven with Morton's kin as her jailers if freeing her from Bothwell's influence was the objective. That could have been achieved in a house arrest at Holyrood or Edinburgh Castle, which is what she had been promised.
Kirkcaldy was beginning to think he had been duped. Thus, three days after spiriting her off to the Douglas stronghold at Loch Leven in the dead of night with little more than the clothes on her back, Morton and Maitland would have been highly motivated to uncover evidence of her direct participation in her husband Darnley's murder, and the letters produced in facsimile at York the following year did just that.
Power players such as Elizabeth Tudor and Catherine de Medici's and her sons, and especially Philip II of Spain were not impressed with the idea of locking up an anointed sovereign on grounds as flimsy as having entered into an unpopular marriage. The Scottish lairds desperately needed a stronger case—one which directly implicated the queen in her second husband Henry Darnley’s murder. Their discovery was an all too convenient surprise.
The discovery of documents that had allegedly been left by Bothwell in his apartments in Edinburgh Castle presents another red flag issue, for at the time, Edinburgh Castle was under the control of Sir James Balfour, and if anyone knew the truth about the events of 1566 and 67, it was Balfour, who was as inconstant as the shifting winds from off the Firth and blew both ways. Contemporaries called him 'the most corrupt man of his age,’ (Robertson’s Hist. vol. ii. p. 354,).
He first appears as a principal in the events leading to consort Darnley's murder in the autumn of 1566 at Craigmiller where the plot to kill the queen's offensive husband was formalized, right under her nose and possibly at her bidding. It is Balfour who allegedly did the drafting and supervised the signing of the mysterious document known as the Craigmillar Bond, which conveniently disappeared in all of its alleged versions and causes some historians to speculate that perhaps it never existed, at least not in the format alluded to by rival historians.
But the few undisputed facts about Craigmillar suggest that indeed a meeting was held there and its results reduced to writing, and that the queen's new champion Bothwell was the person who recruited his friend Balfour to act as scribe. Balfour was probably not present at the early discussions, but he must have been at Craigmillar or nearby, and it was at Bothwell's instigation that he was let into the loop.
Which begs the question, if he was Bothwell's boon friend and henchman, why did the lairds leave him in possession of Edinburgh Castle during the rebellion when the castle was so large a prize? The answer, it seems, was that they had already turned him. And if that is true, that also begs the second question of why they would trust him once their backs were turned?
Another undisputed fact is that after the queen married Bothwell on May 15, she and her new husband believed that if matters deteriorated they could always ride up Castle Hill and deal with their enemies from the safety of Scotland’s most impenetrable fortress. However, when the time came for the excursion up the hill, either Maitland or his emissary James Melville had been there first, because as a result of secret negotiations with Maitland acting as a clandestine agent of the rebel lords, Balfour refused to let the queen and her consort Bothwell enter. Perhaps his continuing governorship of the castle had been the bribe that kept the gates of the castle locked.
Balfour's refusal of entry was not an act without risk. Historically, the Queen of Scots had not dealt kindly with those who denied her access to her castles. In 1562 after she had been denied entry into a royal castle on her march north, she had its captain hung from the battlements. Such an act was considered treason. Balfour’s open act of defiance might have inspired trust in Morton to a limited degree if that had been the end of it. But it was not.
When the queen and Bothwell fled the city and took refuge in Borthwick Castle, Balfour sent a message warning them that an army was hot on their heels. Balfour was a man who played the odds but also hedged his bets. If Morton was aware of Balfour’s double-dealing, and it is hard to believe he was not, his continued reliance on Balfour's loyalty was misplaced, unless of course, he and Maitland had agreed to overlook it, knowing that Balfour could be bought.
So, how did the documents that allegedly implicated the queen end up in Morton's hands? Morton's formal declaration describes the event essentially as follows. He was dining with Maitland in Edinburgh when a man appeared with a message that three men in the service of the Earl of Bothwell had appeared at the castle to take possession of certain of Bothwell's things that had been left behind in early June and to which, as stated above, he had been denied access. Balfour, acting in character, gave the men permission to enter Bothwell's quarters and carry off whatever they willed. Also in character, he sent his messenger to Morton, who interrupted his supper long enough to summon a band of Douglases to hasten up the hill to check it out while he and Maitland continued their repast.
At some later point, Morton and Maitland were informed that only one of the three had been apprehended by Morton's kinsman Robert Douglas in Potters-Row near Edinburgh, and the unfortunate captive was Bothwell's servant George Dalgleish, who indeed had items of clothing and documents from the castle on his person. When the items were brought to Morton for his perusal, he and Maitland considered them to be of no special significance, mostly deeds and grants to properties Bothwell owned. But canny and efficient Morton was suspicious and ordered George Dagleish taken to the Tollbooth to be detained in proximity to the institution’s well known collection of torture devices. and if necessary, subjected to a demonstration.
Dalgleish was overcome with a need to disclose the entire story and thereafter, he led Morton's kinsman Sir Robert Douglas to his rooms in Potter-row and retrieved a silver casket from beneath his bed. The small silver box was delivered by Sir Robert or one of his servants to the Earl of Morton on July 20, possibly again in Maitland's presence. But, alas! It was locked and Dalgleish had not provided a key.
The next installment of the story begs the question of why a man like Morton, who had conducted himself on the battlefields of Corrichie and elsewhere with great audacity and cunning, who had been instrumental in the queen's secretary David Rizzio's grizzly murder, and who had offered himself in hand to-hand combat with the border warrior Bothwell at Carberry less than a week before, would suddenly find himself intimidated by a simple lock on a little silver box at a time when Bothwell was a fugitive and any clue to his whereabouts would have been a major breakthrough.
While it is true that he may not have had enough of a following to be a military threat, there is some evidence that Bothwell had a copy of another bond dealing with the murder of the king, this one signed at Whittinghame by Morton. It is disingenuous to think Morton would have waited till there were witnesses before he culled the contents of the casket so see what was inside. Nevertheless, his sworn statement declared that he waited until the following day to force the dainty little lock in a show witnessed by Maitland and staged for the entertainment of the Earls of Athol, Mar and Glencairn and numerous of the barons.
His declaration does not mention why the items were apparently counted but not otherwise inspected or inventoried. If the box Morton opened on June 21 contained the love poetry, steamy love letters and evidence of matricide Morton and Moray later claimed, would he not have been jumping up and down and shouting the 16th Century Scottish equivalent of Eureka?
According to Morton, the items were left secured and undisturbed in Morton's possession until September at which time they were passed to the custody of Marie's treacherous brother Moray after his sister's coerced abdication. Morton’s self-serving declaration was read to the Commission at Westminster (which had been moved from York at the request of Her Majesty, Queen Elizabeth) on December 9, 1568. Other documents offered in support of the integrity of the evidence--what modern law rules of evidence refer to as 'the chain’ -indicate quite clearly that the box contained twenty-one unspecified documents when it was opened. However, the record of the tribunal reveals that only eleven items, eight of which were deemed significant, were introduced, which, of course, begs the question of what happened to the remainder.
A complete analysis of the Casket Letters is far too comprehensive for a post, but books have been written either in support or in defense of the allegation that the casket letters were the result of an artful bit of forgery and a clever cut and paste job.
Maitland, his wife Marie Flemyng, and another of the Four Maries, Marie Beaton, Lady Boyne, are among the usual suspects. Both Flemyng and Beaton had handwriting nearly indistinguishable from the queen's, and Maitland had the wit to pull it off. It is interesting to note that in recreating a murder plot in which dates were crucial, the letters in their original form apparently were not dated, and some began without customary salutations, and contained awkward phrases unlike Marie Stuart's other writing, even when she was under stress.
The cut and paste theory would explain how portions of twenty-one documents might have been combined to produce the eleven proffered, especially when examining the especially damning letters #1 and #2, which contained Non sequiturs and strange inclusions and omissions that support the proposal that the Casket Letters are a fraud. They also disclosed a clumsy use of idiomatic French, and some rather poor verse unlikely to have been written by a woman who had been educated as a French girl and whose poetry instructor had been the famous Pierre Ronsard. None of the damning documents were presented at the indictment of the Queen before the Scottish Parliament in December, 1567, before Marie Stuart's escape from Loch Leven and unfortunate flight to England, although they were apparently discussed. Indeed it makes one wonder if perhaps the ink was not yet dry.
Although claims of damning documents in the hand-writing of the queen had been leaked to the crowned heads of Europe as well as to Elizabeth and Cecil, the documents were never produced in their original form in any hearing, although there are claims that the chief judge of the tribunal at Norfolk read them. He was apparently not all that impressed of the queen’s homicidal tendencies, because the next year he began a clandestine courtship of the alleged murderess, the first of several political missteps which eventually cost him his head.
It is also important to note that the queen's escape from Loch Leven in the early spring of 1568 was not engineered with intent to flee, but to prevail. Hers was the superior army in terms of raw numbers. With Bothwell out of the picture, much of her popularity and mystique had been restored. While at Carberry in early June 1567 her army was cursed by desertions, the force she led across Scotland in 1568 was growing as it marched. It was the superior leadership of the Regent's army under Morton, Moray and Kirkcaldy that caused her formidable force to come off second best at Langside in 1568, and even that battle need not have been dispositive.
The queen acted in haste in fleeing to England rather than retreating to Dumbarton Castle, held for her by Lord John Fleming. That was what every single voice raised by her advisers had urged. The great northern Catholic earls were headed there with experienced troops and might well have provided the leadership and military experience to change the ultimate outcome. The Parliament which had condemned her a few months earlier had been a handpicked group of anti-Marians whose decision was never in doubt, but it did not reflect the rising tide of Marian support. Her decision to flee was a product of her Stewart impetuousness, a fear of the harsh confinement she had tasted at Loch Leven and a misplaced trust in her cousin Good Queen Bess.
In spite of Elizabeth's minister William Cecil's determination to besmirch the Queen of Scots, and the widespread rumors of condemning letters written in her own hand, the alleged contents of the casket apparently never surfaced in their original state, and were not even circulated in translation until the winter of 1568-69. One explanation for withholding such dynamic evidence is that the letters in the silver casket had not been manufactured yet.
Author's Note:
It is noteworthy that in making her equivocal ruling that the case against her cousin Marie Stuart on the one hand, and the queen's charges against the rebellious lords on the other, had not been proved, Elizabeth Tudor apparently discounted the evidentiary value of the Casket Letters. There is a strong possibility that the original French letters would not have withstood scrutiny by someone with Elizabeth's linguistic expertise. She had always taken great pride is her knowledge of French. Perhaps that is also why the contents of the casket disappeared during the early reign of King James VI. In researching my debut novel The First Marie and the Queen of Scots, I propound an interesting theory of who it was who assisted the Earl of Morton in the commission of one of history's greatest frauds, a question unlikely to be resolved without resort to fiction.
There are several different views as to how this most unlikely discovery surfaced and whether Morton's words are credible.
The first red flag is the dinner itself, because Morton and Maitland were not friends. What bound them together, if anything was the fact that each had the goods on the other. But since the two of them were running Scotland until the queen's half-brother Moray returned from wherever he had gone to stay clear of the fracas that followed his sister's marriage to Bothwell, I concede that perhaps they did have matters to discuss. Moray was due to return in a matter of days, and Morton and Maitland needed to have their ducks lined up.
At that point, while the surrender of the queen had been accepted by the common folk, who had been shocked by her behavior with Bothwell, there were already grumblings coming from the Knight Kirkcaldy of Grange, who had procured the queen's surrender on very specific terms and was of the opinion that her harsh treatment left his honor tarnished. Kirkcaldy had served in France with King Henri Valois in a setting where chivalry was the watchword and a man's honor was everything.
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| Russ Root from The Last Knight |
Kirkcaldy was beginning to think he had been duped. Thus, three days after spiriting her off to the Douglas stronghold at Loch Leven in the dead of night with little more than the clothes on her back, Morton and Maitland would have been highly motivated to uncover evidence of her direct participation in her husband Darnley's murder, and the letters produced in facsimile at York the following year did just that.
Power players such as Elizabeth Tudor and Catherine de Medici's and her sons, and especially Philip II of Spain were not impressed with the idea of locking up an anointed sovereign on grounds as flimsy as having entered into an unpopular marriage. The Scottish lairds desperately needed a stronger case—one which directly implicated the queen in her second husband Henry Darnley’s murder. Their discovery was an all too convenient surprise.The discovery of documents that had allegedly been left by Bothwell in his apartments in Edinburgh Castle presents another red flag issue, for at the time, Edinburgh Castle was under the control of Sir James Balfour, and if anyone knew the truth about the events of 1566 and 67, it was Balfour, who was as inconstant as the shifting winds from off the Firth and blew both ways. Contemporaries called him 'the most corrupt man of his age,’ (Robertson’s Hist. vol. ii. p. 354,).
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| The Balfour Armoral |
He first appears as a principal in the events leading to consort Darnley's murder in the autumn of 1566 at Craigmiller where the plot to kill the queen's offensive husband was formalized, right under her nose and possibly at her bidding. It is Balfour who allegedly did the drafting and supervised the signing of the mysterious document known as the Craigmillar Bond, which conveniently disappeared in all of its alleged versions and causes some historians to speculate that perhaps it never existed, at least not in the format alluded to by rival historians.
But the few undisputed facts about Craigmillar suggest that indeed a meeting was held there and its results reduced to writing, and that the queen's new champion Bothwell was the person who recruited his friend Balfour to act as scribe. Balfour was probably not present at the early discussions, but he must have been at Craigmillar or nearby, and it was at Bothwell's instigation that he was let into the loop. Which begs the question, if he was Bothwell's boon friend and henchman, why did the lairds leave him in possession of Edinburgh Castle during the rebellion when the castle was so large a prize? The answer, it seems, was that they had already turned him. And if that is true, that also begs the second question of why they would trust him once their backs were turned?
Another undisputed fact is that after the queen married Bothwell on May 15, she and her new husband believed that if matters deteriorated they could always ride up Castle Hill and deal with their enemies from the safety of Scotland’s most impenetrable fortress. However, when the time came for the excursion up the hill, either Maitland or his emissary James Melville had been there first, because as a result of secret negotiations with Maitland acting as a clandestine agent of the rebel lords, Balfour refused to let the queen and her consort Bothwell enter. Perhaps his continuing governorship of the castle had been the bribe that kept the gates of the castle locked.
Balfour's refusal of entry was not an act without risk. Historically, the Queen of Scots had not dealt kindly with those who denied her access to her castles. In 1562 after she had been denied entry into a royal castle on her march north, she had its captain hung from the battlements. Such an act was considered treason. Balfour’s open act of defiance might have inspired trust in Morton to a limited degree if that had been the end of it. But it was not.
When the queen and Bothwell fled the city and took refuge in Borthwick Castle, Balfour sent a message warning them that an army was hot on their heels. Balfour was a man who played the odds but also hedged his bets. If Morton was aware of Balfour’s double-dealing, and it is hard to believe he was not, his continued reliance on Balfour's loyalty was misplaced, unless of course, he and Maitland had agreed to overlook it, knowing that Balfour could be bought.
So, how did the documents that allegedly implicated the queen end up in Morton's hands? Morton's formal declaration describes the event essentially as follows. He was dining with Maitland in Edinburgh when a man appeared with a message that three men in the service of the Earl of Bothwell had appeared at the castle to take possession of certain of Bothwell's things that had been left behind in early June and to which, as stated above, he had been denied access. Balfour, acting in character, gave the men permission to enter Bothwell's quarters and carry off whatever they willed. Also in character, he sent his messenger to Morton, who interrupted his supper long enough to summon a band of Douglases to hasten up the hill to check it out while he and Maitland continued their repast.
At some later point, Morton and Maitland were informed that only one of the three had been apprehended by Morton's kinsman Robert Douglas in Potters-Row near Edinburgh, and the unfortunate captive was Bothwell's servant George Dalgleish, who indeed had items of clothing and documents from the castle on his person. When the items were brought to Morton for his perusal, he and Maitland considered them to be of no special significance, mostly deeds and grants to properties Bothwell owned. But canny and efficient Morton was suspicious and ordered George Dagleish taken to the Tollbooth to be detained in proximity to the institution’s well known collection of torture devices. and if necessary, subjected to a demonstration.
Dalgleish was overcome with a need to disclose the entire story and thereafter, he led Morton's kinsman Sir Robert Douglas to his rooms in Potter-row and retrieved a silver casket from beneath his bed. The small silver box was delivered by Sir Robert or one of his servants to the Earl of Morton on July 20, possibly again in Maitland's presence. But, alas! It was locked and Dalgleish had not provided a key.
The next installment of the story begs the question of why a man like Morton, who had conducted himself on the battlefields of Corrichie and elsewhere with great audacity and cunning, who had been instrumental in the queen's secretary David Rizzio's grizzly murder, and who had offered himself in hand to-hand combat with the border warrior Bothwell at Carberry less than a week before, would suddenly find himself intimidated by a simple lock on a little silver box at a time when Bothwell was a fugitive and any clue to his whereabouts would have been a major breakthrough.
While it is true that he may not have had enough of a following to be a military threat, there is some evidence that Bothwell had a copy of another bond dealing with the murder of the king, this one signed at Whittinghame by Morton. It is disingenuous to think Morton would have waited till there were witnesses before he culled the contents of the casket so see what was inside. Nevertheless, his sworn statement declared that he waited until the following day to force the dainty little lock in a show witnessed by Maitland and staged for the entertainment of the Earls of Athol, Mar and Glencairn and numerous of the barons.
His declaration does not mention why the items were apparently counted but not otherwise inspected or inventoried. If the box Morton opened on June 21 contained the love poetry, steamy love letters and evidence of matricide Morton and Moray later claimed, would he not have been jumping up and down and shouting the 16th Century Scottish equivalent of Eureka?
According to Morton, the items were left secured and undisturbed in Morton's possession until September at which time they were passed to the custody of Marie's treacherous brother Moray after his sister's coerced abdication. Morton’s self-serving declaration was read to the Commission at Westminster (which had been moved from York at the request of Her Majesty, Queen Elizabeth) on December 9, 1568. Other documents offered in support of the integrity of the evidence--what modern law rules of evidence refer to as 'the chain’ -indicate quite clearly that the box contained twenty-one unspecified documents when it was opened. However, the record of the tribunal reveals that only eleven items, eight of which were deemed significant, were introduced, which, of course, begs the question of what happened to the remainder.
A complete analysis of the Casket Letters is far too comprehensive for a post, but books have been written either in support or in defense of the allegation that the casket letters were the result of an artful bit of forgery and a clever cut and paste job.
Maitland, his wife Marie Flemyng, and another of the Four Maries, Marie Beaton, Lady Boyne, are among the usual suspects. Both Flemyng and Beaton had handwriting nearly indistinguishable from the queen's, and Maitland had the wit to pull it off. It is interesting to note that in recreating a murder plot in which dates were crucial, the letters in their original form apparently were not dated, and some began without customary salutations, and contained awkward phrases unlike Marie Stuart's other writing, even when she was under stress.
The cut and paste theory would explain how portions of twenty-one documents might have been combined to produce the eleven proffered, especially when examining the especially damning letters #1 and #2, which contained Non sequiturs and strange inclusions and omissions that support the proposal that the Casket Letters are a fraud. They also disclosed a clumsy use of idiomatic French, and some rather poor verse unlikely to have been written by a woman who had been educated as a French girl and whose poetry instructor had been the famous Pierre Ronsard. None of the damning documents were presented at the indictment of the Queen before the Scottish Parliament in December, 1567, before Marie Stuart's escape from Loch Leven and unfortunate flight to England, although they were apparently discussed. Indeed it makes one wonder if perhaps the ink was not yet dry.
Although claims of damning documents in the hand-writing of the queen had been leaked to the crowned heads of Europe as well as to Elizabeth and Cecil, the documents were never produced in their original form in any hearing, although there are claims that the chief judge of the tribunal at Norfolk read them. He was apparently not all that impressed of the queen’s homicidal tendencies, because the next year he began a clandestine courtship of the alleged murderess, the first of several political missteps which eventually cost him his head.
It is also important to note that the queen's escape from Loch Leven in the early spring of 1568 was not engineered with intent to flee, but to prevail. Hers was the superior army in terms of raw numbers. With Bothwell out of the picture, much of her popularity and mystique had been restored. While at Carberry in early June 1567 her army was cursed by desertions, the force she led across Scotland in 1568 was growing as it marched. It was the superior leadership of the Regent's army under Morton, Moray and Kirkcaldy that caused her formidable force to come off second best at Langside in 1568, and even that battle need not have been dispositive.
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| Russ Root "Defeat" |
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| Dumbarton Castle |
Author's Note:
It is noteworthy that in making her equivocal ruling that the case against her cousin Marie Stuart on the one hand, and the queen's charges against the rebellious lords on the other, had not been proved, Elizabeth Tudor apparently discounted the evidentiary value of the Casket Letters. There is a strong possibility that the original French letters would not have withstood scrutiny by someone with Elizabeth's linguistic expertise. She had always taken great pride is her knowledge of French. Perhaps that is also why the contents of the casket disappeared during the early reign of King James VI. In researching my debut novel The First Marie and the Queen of Scots, I propound an interesting theory of who it was who assisted the Earl of Morton in the commission of one of history's greatest frauds, a question unlikely to be resolved without resort to fiction.
It's hard to judge the authenticity of the letters simply by their text. As I understand it, what we have are all very poor translations from the original French (even our "French" copies appear to have been translated from another language, probably Scots or English.)
ReplyDeleteAnd, no, the letters did surface in their original state. They seem to have been exhibited privately to at least some members of the Scottish Parliament, although they were not "officially" produced. Reading between the lines of everyone's behavior strongly indicates that the original letters contained some kind of information that Mary's enemies wished to keep hidden. It's obviously too long a story to go into in a mere blog comment, but I believe that if the texts were tampered with during copying and translating, it was to keep material out, not to put material damaging to Mary in. Keep in mind, the letters themselves as we have them are not really proof of anything against Mary other than that she was in love with Bothwell, who was everyone's designated patsy for the Darnley murder.
The successive Regents all kept the originals of the letters--it seems to have been a sort of "sacred trust." It was not an easy task, as both Mary and Elizabeth's government were very anxious to get hold of those originals themselves. After the last Regent, the Earl of Morton, was executed in 1581, the originals of the letters somehow wound up in the possession of the Earl of Gowrie. The English Ambassador did his best to get the letters from Gowrie, but the Earl refused.
In 1584 King James suddenly had Gowrie arrested and executed, and it is only after that that the location of the letters becomes murky. Some assume James got his hands on them and destroyed them, but that seems to be only supposition. There were various "sightings" of the original letters as late as the mid 18th century.
For all we know, they still exist somewhere--and wouldn't THAT be one of the all-time great historical finds!
P.S. I take it your novel champions the theory that Maitland of Lethington put up his wife Mary Fleming to forge the letters. I've never bought that idea. Aside from the fact that neither had a motive--or really, the time to do such work--Maitland was the one who secretly sent Mary copies of the letters right before the 1568 conference. Why would he forge letters and then send his victim, who would surely know they were fake, copies for inspection and denunciation?
Incidentally, Mary never did directly state the letters were fake. The most she said was a carefully-worded statement declaring that she never wrote anything concerning Darnley's murder, and if any documents, claimed to be in her hand, ever appeared dealing WITH THAT SUBJECT, they were forgeries. The letters, of course, never explicitly talked of Darnley's murder at all. I've always read that as Mary tacitly admitting that the Casket Letters were genuine.