Mary, Queen of Scots, was executed due to her suspected involvement in the Babington Plot, a conspiracy aiming to assassinate Queen Elizabeth I and place Mary on the English throne. After being imprisoned for nearly 19 years, Mary was a figure enmeshed in the political and religious turmoil of the time, representing Catholic claims to the Elizabethan crown. The Babington Plot, orchestrated in 1586 by a group of English Catholics, aimed to enlist Spanish support for the assassination of Elizabeth and liberate Mary.

Mary had become a focal point for Catholic supporters who opposed Elizabeth's Protestant rule, leading her to be seen both as a victim and a threat. Though she denied knowledge of the plot, her correspondence was intercepted and presented as evidence of her complicity. In the lead-up to her execution, she was granted a last request to write a letter to Elizabeth, hoping for forgiveness or at least a chance to appeal her sentence. However, Elizabeth's council insisted on proceeding with the execution, ultimately leading to Mary's beheading at Fotheringhay Castle.

The execution took place amid a tense atmosphere, where Mary reportedly showed dignity, reciting the words of the Catholic Mass prior to her death. She met her end on the scaffold, where her last words reflected her unwavering faith and belief in her divine right to rule. The event marked a significant moment of political maneuvering, influenced by fears of an uprising and foreign intervention, leading to heightened tensions between Catholics and Protestants in England and beyond.