'Oh, Lord! The Queen is a woman!'
That was the reaction of one of Elizabeth's subjects upon seeing her for the first time. Elizabeth had some very serious negative expectations of a woman leader to overcome. She was unmarried and childless when she succeeded her half-sister, Mary I, on 17 November 1558. Mary, the first English queen in her own right, had also been unmarried at her accession. She insisted on marrying Prince Philip of Spain (later Philip II) despite the division in her council on the matter and against popular opinion. With this alliance, Mary constantly deferred to Philip for decisions and England quickly became a pawn in Spain's war with France.
Mary, a devout Roman Catholic, also reversed the Reformation begun by her father, returning church power to Rome and enforcing a campaign of harsh persecutions for those who would not conform. Mary always put principles first and during her reign about 300 people were burned at the stake for being 'heretics', earning her the name of 'Bloody Mary'.
For much of the time, Elizabeth was proving herself against the model of Mary, in order to convince her subjects that a woman could rule and rule well. In opposition to Mary, she was determined to rule by head over heart, to favour considered advice over unwavering principles, and support moderation and compromise over extremism and fanaticism. She also learned that public opinion and popularity were definitely important.