Elizabeth was the legitimate heir only in Protestant eyes; many Catholics preferred Mary Stuart, Queen of Scotland. Mary Stuart was the daughter of James V of Scotland and Mary of Guise. In November 1542 at the age of one week, she became Queen of Scotland. When she was sent to France to be educated, her mother remained in Scotland as regent.

In 1557 Scottish nobles formed a “Congregation of Christ” to work for the establishment of the reformed religion in Scotland. After John Knox led a rebellion against the French dominated government of Scotland, French troops agreed to withdraw, and a new government was appointed by Mary and the Scottish parliament (Treaty of Edinburgh, July 1560).

Mary Stuart was forced to abdicate in July 1567 after being implicated in her husband’s murder. She appealed for help from her cousin Elizabeth who put her under house arrest. Unfortunately, Mary soon became a magnet for rebellion. In 1569 she was the central figure in a plot to replace Elizabeth with herself and the Duke of Norfolk, thereby restoring Catholicism to England. The Pope tried to aid the Catholic cause by excommunicating Elizabeth (Regnans in Excelsis, 1570). In March 1571 Mary was involved in a plot by Robert Ridolfi to once more replace Elizabeth with Mary and Norfolk. Mary’s participation in the Babington Plot of 1586 ultimately brought her downfall. In February 1587 she was executed.

The greatest foreign danger to Elizabethan Protestantism came from Philip II of Spain. A number of modern historians, such as David Howarth in his 1981 study of the Armada, dispute the Tudor version of the Spanish/English engagement as a Protestant miracle. Howarth argues that the strategic plan devised by Philip was impractical and unworkable. The Duke of Medina Sidonia, who was put in charge of the Armada, was chosen for his social rank. The Duke of Parma, whom Philip ordered to join Sidonia mid journey, was trapped in the shallow Dutch harbors. The Spanish ships were designed to ferry soldiers and cannon across the channel for a land battle.

The English fleet was commanded by the most famous sea captains of the age – Lord Howard, Sir Francis Drake, John Hawkyns. Their ships were built for speed and agility. The English also had the advantage of home ports.

The Battle of Gravelines (August 1588) was disastrous for the Spanish, and their heavy ships were unable to return the way they had come. Instead, they set a northerly course for Spain (around the British Isles) where they were wrecked on the coasts of Scotland, Ireland, and England. Of the 30,000 men who had set sail in June 1588, two-thirds perished from battle, shipwreck, or disease. The primary fault for the fiasco, Howarth believes, lay with Philip.