Why did Mary Queen of Scots arrival in England in 1568 cause problems for Elizabeth?

BackgroundMary fled into England in May 1568, having been defeated by her Scottish nobles. Following the murder of her dashing but difficult husband Henry Darnley, Mary had responded by marrying the man everyone in Scotland suspected of committing the crime. The Scottish people were outraged at her behaviour and her nobles named her baby son the new monarch in her place. (1) NATIONAL AFFAIRSThe English reformation had begun under Elizabeth's father Henry VIII (can you remember the rhyme?), but not everyone embraced the new religion or agreed what it meant – even in the King's own family. From the 1540s, a series of monarchs, all Henry's children, acceded to the throne and altered or totally reversed the religious changes of their predecessors – remember, the monarch decided the religion of the entire nation! So, when the Protestant Elizabeth came to the throne, Catholics in England were permitted to worship as such privately but could reasonably have hoped for another change of monarch, a potentially Catholic monarch. Elizabeth had to be very careful in her treatment of Mary not to annoy her Catholic subjects and to avoid being seen as a persecutor of Catholics, on whom she depended for political loyalty. Mistreating Mary when she was in England and without a kingdom of her own was a potential danger, as English Catholic nobles might rally around her in a rebellion/takeover, giving Elizabeth's crown to her in the process. Crucially, Mary was the legitimate heir to the English throne to most English subjects, and to many Catholics was more deserving than even Elizabeth, who they viewed as illegitimate. Lastly, even if Elizabeth could defeat such a rebellion, she was always worried about the long-term effect that the lawful execution of a monarch would have on the perception of English monarchy (civil war!). International Affairs: As the leader of a small nation with limited resources, Elizabeth wanted to maintain good terms with England's powerful European neighbours and avoid religious war. King Phillip II ruled the most powerful country of the region, Spain, and he was determined that Catholics would have the upper hand across Europe. Disrespect/mistreatment/persecution of Catholics or fellow legitimate monarchs (he did not include Elizabeth in this group!) would not be tolerated (as was the case when he sent the Armada in 1588 following the execution of Mary the previous year by Elizabeth). Elizabeth had to keep Spain in mind. To support her against potential Spanish hostility, Elizabeth also needed France to help her. However, as Mary was a dowager French Queen and enjoyed a close personal relationship with the French royal family, treating Mary respectfully according to her French, Scottish, and English station, and her religion, was very important. Elizabeth had to balance these needs against those of Scotland. If she acknowledged Mary as legitimate Scottish monarch, refused to rebuke her for her behaviour, or offered her any kind military support to reclaim her country and crown, she might risk war with the new Scottish regime, a protestant one which she might need against Catholic Spain or France.