All substantial threats to Elizabeth’s position as Queen were symptoms of the tension between Catholicism and Protestantism. The threats posed by Mary Queen of Scots, as well as those of the Spanish Armada of 1588 and the war with Spain (which dominated the last twenty years of Elizabeth’s reign), were consequences of a Catholic desire to gain supremacy in England. However, the extent to which the Catholic threat was centred on Mary Queen of Scots is debateable. Whilst she was undoubtedly a figurehead for Catholic opposition to Elizabeth’s rule and was the monarchical figure around whom several treasonous plots were designed, there is much evidence for the view that Mary became a focal point for a Catholic threat that would have existed even if she had been absent. The extent to which the structure given to the Catholic cause by Mary’s presence strengthened the Catholic threat is also debateable. There were others who could have become the rallying point for Catholic opposition (as Philip II of Spain did after Mary’s death), although none had as good a claim to the throne as Mary. A great threat was presented by Catholic opposition to Elizabeth’s rule, but Mary’s influence over this, and therefore the threat that she posed as an individual, may be called into question.
One way in which Mary was central to the Catholic threat was through her part in various plots to overthrow Elizabeth. The Rebellion of the Northern Earls in 1569 was the first of these to present an overt challenge to Elizabeth’s authority. The Earls’ aim was to see Mary married to a Catholic and recognised as the heir to the throne of England. Several courtiers suggested the Duke of Norfolk (who was formally a protestant but may well have had Catholic sympathies) marry Mary. When Elizabeth learnt of this she summoned Norfolk to Court and ordered that he lodge in the Tower. The Earl of Westmorland (who was married to Norfolk’s