The news stunned Queen Elizabeth I and her court. Her cousin Mary, Queen of Scots had been defeated on the battlefield near Glasgow and fled in terror of being captured. Crossing the border to England she had arrived in Carlisle with nothing but the clothes she stood up in. It was May, 1568.Mary (that's her on the left) wrote to Elizabeth asking for her support to storm back to Scotland at the head of an army to vanquish her foes. Those foes were led by Mary's half-brother, the Earl of Moray, who just months before had forced her (at knife point, she said) to abdicate. He had also accused her of adultery with the Earl of Bothwell and of conspiring with him to murder her husband, Lord Darnley.Welcome to the shark-infested world of 16th-century Scottish politics.Darnley had indeed been murdered the year previously when the house he was staying in near Edinburgh was blown up. It had been undermined with kegs of gunpowder. Charges for masterminding the crime were laid against Bothwell, the tough military man Mary had turned to when her marriage had soured. There had been plenty of gossip that she and Bothwell were lovers. At his trial Bothwell was acquitted, thanks to Mary's support, and three months after Darnley's death she took Bothwell as her husband.Moray and his followers then accused Maryof the murder. They imprisoned her and forced her to abdicate. Mary had lost her kingdom. Bothwell fled to Denmark.But Mary escaped, raised an army, and met Moray on the Glasgow battlefield. He won. Mary had lost her kingdom for the second time. She was twenty-six.Arriving in England as a royal refugee, Mary fully expected her cousin Elizabeth's protection and support. Mary was often blind to reality when she had a passionate stake in a situation, and never was she more blind than when she asked for help from Elizabeth. (That's Elizabeth below.)Because Mary's arrival in England created a terrible quandary for Elizabeth. England was Protestant but a large, disgruntled portion of its people were Catholics who believed that Mary, a pious Catholic, should be on the throne instead of Elizabeth, whom they regarded as illegitimate and a heretic. Both queens had Tudor blood. Elizabeth was the granddaughter of the first Tudor monarch, Henry VII; Mary was his great-granddaughter. Elizabeth, unmarried, had no children (she was thirty-five), and Mary had the best claim to succeed her. Elizabeth feared that Mary would be a lightning rod for these disaffected Catholics to rise up to put her on the throne. Mary could expect the backing, too, of the mightiest power in Europe, Catholic Spain.Elizabeth's councilors were appalled at the thought of Mary moving freely in England to draw Catholics to her cause, and they advised Elizabeth to imprison Mary. Elizabeth recoiled at that, for she took very seriously her cousin's royal status. However, she decided on a way to neutralize Mary. She could not lend her support, even to a queen, if Mary proved to be an adulteress and a murderer. Here's the dead Lord Darnley.The solution was Machiavellian - and pure Elizabeth. She decided to hold an inquiry into the charges against Mary. In soothing letters to her cousin she assured her that if the charges proved unfounded, as Mary claimed, Elizabeth would wholeheartedly back her in restoring her to her Scottish throne. All of Europe was agog, waiting for the outcome. Elizabeth's tactic was one that modern-day crafters of smear campaigns would appreciate. Dirt, once it is hurled in public, tends to stick. Elizabeth would then be free to uphold her alliance with Moray's Protestant government in Scotland.It was not called a trial, since English courts had no jurisdiction over foreign rulers, but for all intents and purposes a trial is what it was. Elizabeth set the venue; the inquiry would take place at York. (It would later move to Westminster.) She invited the Earl of Moray to come and argue his case before her commissioners. He eagerly agreed, and set out from Edinburgh with a rookery of lawyers.Mary was furious. She refused to attend the inquiry, saying that the only way she would appear to answer the charges made by her subjects was if they were brought before her in chains. It was one of her many impetuous decisions that doomed her, for by all accounts she had extraordinary charm and had she attended she might very possibly have won the commissioners' sympathy. Instead, she appointed others to act in her name: Lord Herries and the Bishop of Ross, men staunchly loyal to her.Elizabeth appointed the Duke of Norfolk to preside. But Norfolk, like just about everyone involved in this intricate piece of political theater, had a hidden agenda. Mary, ever seeking to enhance her power base in England, had made Norfolk an offer he could not resist: marriage. Secretly, in letters, the two formed a marriage plan. For Norfolk it was the brass ring, because Mary had the best claim to be Elizabeth's heir, and if she came to the throne then he, as her husband, would be king. Norfolk, therefore, was secretly predisposed to find Mary innocent.But then something happened that changed the course of the proceedings, and of history. Moray presented evidence to the English commissioners: eight letters written by Mary to Bothwell while she was married to Darnley. These have become known as the "casket letters," so named because, said Moray, they were found in a small silver casket under a bed in Bothwell's house after he had fled the country.How convenient, Mary raged. She had good reason to rage, for she only heard about the letters from leaks. Moray had presented them to Elizabeth's commissioners alone, in secret. Mary was not allowed to see the evidence that was to damn her.And damning it was. The letters were lascivious, the intimate words of a woman to her lover. Worse, they indicated that Mary and Bothwell had indeed been plotting to kill Darnley. News of the letters, carefully leaked, shocked all of Europe. Here's Bothwell.Mary swore to her dying day that the letters were forged. And the fact that she was allowed no rebuttal was such a miscarriage of justice, her furious commissioners withdrew from the inquiry in protest.Elizabeth gave Mary one last chance to come before the inquiry and defend herself. Mary refused, sure that such a desperate move would be a virtual confession of guilt. But the damage had been done. Mary's reputation was in tatters. Even many of her Catholic followers turned away from her.Elizabeth was satisfied. She wrapped up the inquiry without even proclaiming a verdict. She didn't have to.The casket letters no longer exist. Moray took them back to Scotland where they eventually ended up in the possession of Mary's son, James. He became king, and the letters were never seen again.Mary never regained her freedom. She was kept under house arrest for the next nineteen years. Hers was a comfortable captivity, spent in a series of old castles with a small retinue to serve her, but it was captivity nonetheless. During those nineteen years she plotted ceaselessly to take Elizabeth's crown, and when the last plot in 1586 almost succeeded her complicity was an irrefutable fact. Elizabeth had had enough. Charged with conspiring to murder Elizabeth, Mary's trial took place in October 1586. This time, it was not her reputation that was in jeopardy, it was her life.That trial was a mere formality, its outcome never in question. Four months later Mary was executed, beheaded at Fotheringhay Castle.The famous rivalry between these two queens has enthralled the world for over four hundred years. It enthralls us still.___________________________The "casket letters" inquiry forms the backdrop of my novelVisit my website www.BarbaraKyle.com