Anthony Babington was a young Catholic noble who joined a plot to depose the Protestant Queen Elizabeth I and put Mary Queen of Scots on the English throne. Sir Francis Walsingham, the head of Elizabeth’s secret service, captured a Catholic plotter named Gilbert Gifford and ‘convinced’ him to act as a double agent. Gifford would act as an intermediary – smuggling letters to Mary who was imprisoned in Chartley Hall. All the letters were given to Walsingham.
The letters were written in a secret code called ‘a nomenclator cipher’. Walsingham had the code deciphered. Walsingham waited and gathered evidence that would implicate Mary in a plot against Queen Elizabeth. On 28 June 1585 Babington wrote to Mary outlining a plot to murder Elizabeth and release Mary with the support from an invasion from Spain. Myself with ten gentlemen and a hundred of our followers will undertake the delivery of your royal person from the hands of your enemies.
For the dispatch of the usurper, from the obedience of whom we are by the excommunication of her made free, there be six noble gentlemen, all my private friends, who for the zeal they bear to the Catholic cause and your Majesty’s service will undertake that tragical execution. Extract from Anthony Babington letter to Mary, June 1585 Mary’s reply was intercepted and sent to Walsingham. It was sealed with a drawing of a gallows. Walsingham had the evidence he needed.
Babington and the other plotters were arrested, tortured, tried and condemned to be hanged, drawn and quartered. The damning evidence of the letters between Mary and the plotters was presented to Queen Elizabeth. It was only a matter of time before Mary would be sentenced to death. The plot grew out of two originally separate plans. The first involved a Spanish invasion of England with the purpose of deposing Elizabeth and replacing her with Mary; the second was a plot by English Catholics to assassinate Elizabeth.
However, both plots were hatched under the guidance of two of Mary’s chief agents in Europe, Charles Paget and Thomas Morgan, the latter being Mary’s chief cipher clerk for all her French correspondence. King Philip II of England and the Spanish ambassador to England Don Bernardino de Mendoza had been trying to re-establish Spanish influence in English affairs which had been considerably diminished by the death of Mary I of Spain in 1558, not the least through various marriage proposals to Elizabeth (including by Philip himself, who was Mary I’s widower).
As it became evident that Elizabeth was not inclined to accept such proposals, the only alternative would be to depose her and replace her with someone more receptive to their interests, and Mary was the best candidate. Ever since the issuance of the papal bull Regnans in Excelsis by Pope Pius V on February 25, 1570, Philip was prepared to assist English Catholics who plotted to overthrow the English queen. It was thus with the support of the papacy and Spain that Morgan and Paget sought to find those in England who would be prepared to meet this objective.