The Catholic threat: Northern Earls, plots and Mary Queen of Scots
The Catholic Threat to Elizabeth
In the early years of her reign, Elizabeth adopted a policy of limited tolerance towards English Catholics. The Religious Settlement fined recusants but did not imprison them for their faith alone. However, from 1570 onwards the Catholic threat intensified significantly. A combination of papal action, foreign intervention and the presence of a rival claimant to the throne — Mary Queen of Scots — transformed the religious problem into an existential political crisis.
Excommunication, 1570
In February 1570, Pope Pius V issued the papal bull Regnans in Excelsis. This formally excommunicated Elizabeth — declared her a heretic and expelled her from the Catholic Church. More dangerously, it also released all Catholic subjects from their duty to obey her, effectively calling on Catholics to overthrow her. This transformed recusancy from a matter of personal religious conscience into a matter of political treason. Every Catholic who remained loyal to Rome could now be seen as a potential traitor.
Pope Pius V’s bull Regnans in Excelsis (1570) excommunicated Elizabeth and released Catholics from obedience to her. This made every Catholic potentially suspect of treason, hardened the government’s response to recusancy, and prompted the Ridolfi Plot of 1571.
The Northern Rebellion, 1569
The Northern Rebellion of 1569 (also known as the Rebellion of the Northern Earls) was the most serious internal military threat of Elizabeth’s reign. The earls of Northumberland and Westmorland led a force of approximately 5,000 men south from Durham, celebrating Catholic Mass and carrying banners of the Five Wounds of Christ — a symbol associated with the 1536 Pilgrimage of Grace. Their aims were to free Mary Queen of Scots, who had arrived in England in 1568 seeking refuge, and to restore Catholicism to England.
The rebellion collapsed without any significant battle. Queen Elizabeth moved Mary further south to prevent her rescue, the expected Spanish support from Philip II never materialised, and southern England did not rise in support. By February 1570, the earls had fled to Scotland. About 600 rebels were executed — a deliberately harsh response to deter future revolt. The collapse of the rebellion demonstrated Elizabeth’s firm control over most of England, but it also confirmed that the north remained a centre of Catholic sympathy.
The Three Catholic Plots
Between 1571 and 1586, three major Catholic plots threatened Elizabeth’s life. All three centred on plans to assassinate or depose Elizabeth and replace her with Mary Queen of Scots, supported by foreign Catholic powers.
Roberto Ridolfi was an Italian banker based in London who organised a plot in 1571 to assassinate Elizabeth, install Mary Queen of Scots as queen, and secure a Spanish invasion led by the Duke of Alva from the Netherlands. The English co-conspirator was the Duke of Norfolk — England’s leading Catholic nobleman, who had previously proposed marrying Mary. The plot was uncovered by Elizabeth’s intelligence network. Norfolk was executed in 1572. Elizabeth refused to execute Mary, despite Parliament’s demands, arguing that executing a fellow monarch would set a dangerous precedent.
The Throckmorton Plot of 1583 involved Francis Throckmorton, who was passing messages between Mary and the Spanish ambassador Bernadino de Mendoza, with a plan for a French Catholic army (led by the Duke of Guise) to invade England. Walsingham’s agents uncovered the plot; Throckmorton was tortured, confessed and executed in 1584. Mendoza was expelled from England.
The Babington Plot of 1586 was the most dangerous. Anthony Babington and a group of Catholic gentlemen planned to assassinate Elizabeth, free Mary from captivity and receive Spanish military support. Crucially, Walsingham’s agents had infiltrated the plot and were secretly reading all the letters exchanged between Babington and Mary. Mary’s letters included explicit approval of Elizabeth’s assassination — this was the evidence Walsingham needed. The conspirators were arrested and executed. Mary’s written approval of the plot finally gave Elizabeth and her Council the legal justification to put her on trial.
Mary Queen of Scots
Mary Stuart (1542–1587) was the daughter of James V of Scotland and Mary of Guise, and a granddaughter of Henry VIII’s sister Margaret Tudor. This lineage made her a credible claimant to the English throne, particularly in Catholic eyes, since they did not recognise Elizabeth’s legitimacy. Mary had been Queen of France and Queen of Scotland before being forced to abdicate in 1567. She fled to England in 1568 seeking Elizabeth’s protection — and found herself instead under house arrest, detained as a threat for nineteen years.
Despite repeated pressure from Parliament and her Council, Elizabeth was deeply reluctant to execute Mary. She argued that executing an anointed monarch was sacrilege and would set a precedent that could be used against herself. After the Babington Plot, however, the evidence was irrefutable: Mary had knowingly approved a plan to murder Elizabeth. Parliament passed the Bond of Association (1584), requiring signatories to hunt down and execute anyone in whose name a plot against Elizabeth was carried out. This was designed specifically to provide a legal basis for Mary’s death. Mary was put on trial, found guilty of treason and executed at Fotheringhay Castle on 8 February 1587.
Mary Queen of Scots was executed on 8 February 1587 at Fotheringhay Castle. The decisive evidence was her own letters, intercepted by Walsingham’s agents, in which she explicitly approved Anthony Babington’s plan to assassinate Elizabeth.