Mary Queen of Scots was executed on February 8, 1587, at Fotheringhay Castle in England. She was beheaded for treason after being convicted of plotting to assassinate her cousin, Queen Elizabeth I. But the real reasons ran deeper than a single conspiracy. Mary’s death was the result of nearly two decades of political tension, religious conflict, and a dangerous claim to the English throne that made her a permanent threat to Elizabeth’s reign.
A Catholic Queen With a Claim to England
Mary Stuart was Elizabeth I’s second cousin, and through her lineage she held a legitimate claim to the English throne. Many Catholics in England and across Europe considered her claim stronger than Elizabeth’s, since they viewed Elizabeth, the daughter of Anne Boleyn, as illegitimate. This made Mary far more than a deposed Scottish queen living in exile. She was a living symbol of Catholic resistance to Protestant rule and a rallying point for anyone who wanted to see England return to Catholicism.
Mary had arrived in England in 1568 after being forced to abdicate the Scottish throne. Rather than offering her freedom, Elizabeth placed her under house arrest, a captivity that would last 19 years. Elizabeth couldn’t release Mary without empowering Catholic conspirators, but she also couldn’t easily execute a fellow queen without setting a dangerous precedent. So Mary remained imprisoned, closely watched, and increasingly desperate.
The Babington Plot
What ultimately sealed Mary’s fate was the Babington Plot of 1586, a conspiracy led by a young Catholic nobleman named Anthony Babington. The plan was straightforward: assassinate Elizabeth, free Mary, and place her on the English throne with support from Catholic Spain. Mary communicated with the conspirators through coded letters smuggled in and out of her prison inside beer barrels.
What Mary didn’t know was that Elizabeth’s spymaster, Sir Francis Walsingham, had been intercepting and decoding her correspondence. Mary used ciphers that substituted symbols, numbers, and even zodiac signs for letters and words. Her papers, seized after the plot’s discovery, contained more than 100 different ciphers. Walsingham employed intelligence workers specifically to break these codes, and they succeeded. The decoded letters showed Mary had given her written approval for Elizabeth’s assassination.
Whether Walsingham manipulated evidence to entrap Mary remains debated, but the result was decisive. Mary was put on trial at Fotheringhay Castle in October 1586, found guilty, and sentenced to death on October 25 of that year.
Elizabeth’s Reluctance to Sign
Even with a death sentence in hand, executing Mary was not simple. Elizabeth hesitated for months. Killing an anointed queen, even one convicted of treason, was an extraordinary act. It could provoke invasion from Catholic Spain or France, and it set a precedent that monarchs could be tried and executed by other monarchs. Elizabeth also seems to have been genuinely conflicted about ordering the death of her own cousin.
Her Privy Council pressured her relentlessly. In the end, the council practically had to trick her into signing the warrant, then acted quickly before she could change her mind. Elizabeth was reportedly furious when she learned the execution had been carried out, punishing the councilors who had rushed the warrant through. Whether her anger was genuine or political theater designed to distance herself from the act is something historians still argue over.
Mary’s Final Performance
Mary approached her execution as a carefully staged act of defiance. In a letter written to her brother-in-law, King Henry III of France, she told him she was dying not for treason but for her Catholic faith. In an earlier letter to the Spanish ambassador, written after she learned of her death sentence, she described hearing construction in the great hall of her prison and remarked: “I think it is to make a scaffold to have me play out the final act of the tragedy.”
On the scaffold, she carried a crucifix and wore a petticoat in deep red, the color of Catholic martyrdom. She understood that how she died would shape how she was remembered. The English government wanted the world to see a traitor punished. Mary wanted the world to see a queen murdered for her faith. Given how enduring the image of Mary as a martyr became in the decades and centuries that followed, she largely succeeded.
What Happened After Her Death
Mary’s body was not returned to her family. She was buried at Peterborough Cathedral on August 1, 1587, nearly six months after her execution. The coffin was interred near the resting place of Catherine of Aragon, without ceremony. One recorded reason for the delay was that hot weather might cause the solder on her lead coffin to fail.
Mary’s correspondence with the king of Spain, which had come to light during the Babington investigation, had consequences beyond her own death. Historians have argued it helped accelerate Philip II’s decision to launch the Spanish Armada against England in 1588, the very invasion Elizabeth had feared.
Mary’s son, James VI of Scotland, did not attempt to rescue his mother or avenge her death during Elizabeth’s lifetime. But after Elizabeth died childless in 1603, James inherited the English throne as James I, uniting the crowns of England and Scotland. In 1612, he ordered his mother’s body exhumed from Peterborough and reburied at Westminster Abbey, where she lies today in a tomb grander than Elizabeth’s own, positioned directly across the aisle from her cousin’s.