Overview
The Ridolfi plot was a Catholic plot in 1571 to overthrow Queen Elizabeth I of England and replace her with Mary, Queen of Scots. The plot was hatched and planned by Roberto Ridolfi, an international banker who was able to travel between Brussels, Rome and Madrid to gather support without attracting too much suspicion.
Background
Thomas Howard, 4th Duke of Norfolk, a Roman Catholic with a Protestant education, cousin of Queen Elizabeth's and the wealthiest landowner in the country, had been proposed as a possible husband for Mary since her imprisonment in 1568. This suited Norfolk, who had ambitions and felt Elizabeth persistently undervalued him. In pursuit of his goals, he agreed to support the Northern Rebellion, though he quickly lost his nerve. Norfolk was imprisoned in the Tower of London for nine months and only freed under house arrest when he confessed all and begged for mercy. Pope Pius V, in his 1570 papal bull Regnans in Excelsis, excommunicated the Protestant Elizabeth and permitted all faithful Catholics to do all they could to depose her. The majority of English Catholics ignored the bull, but in response to it, Elizabeth became much harsher to Catholics and their sympathisers.
Plot
Roberto Ridolfi, a Florentine banker and ardent Roman Catholic, had been involved in the planning of the Northern rebellion and had been plotting to overthrow Elizabeth as early as 1569. With the failure of the rebellion, he concluded that foreign intervention was needed to restore Catholicism and bring Mary to the English throne, and so he began to contact potential conspirators. Mary's advisor, John Lesley, the Bishop of Ross, gave his assent to the plot as the way to free Mary. The plan was to have the Duke of Alba invade from the Netherlands with 10,000 men, foment a rebellion of the northern English nobility, murder Elizabeth, and marry Mary to Thomas Howard. Ridolfi optimistically estimated half of all English peers were Catholic and could muster in excess of 39,000 men. Norfolk verbally assured Ridolfi that he was a Catholic, guarantee that was true despite the fact that the Duke had been raised as a Protestant as a child. Both Mary and Norfolk, desperate to remedy their respective situations, agreed to the plot.
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