Editing Ridolfi plot (section)

==Background==
[[Thomas Howard, 4th Duke of Norfolk]], a Roman Catholic with a Protestant education, a second cousin of Queen Elizabeth's and the wealthiest landowner in the country, had been proposed as a possible husband for Mary since her imprisonment in 1568. This suited Norfolk, who had ambitions and felt Elizabeth persistently undervalued him.{{sfn|Williams|1972|p=91|ps=}} In pursuit of his goals, he agreed to support the [[Northern Rebellion]], though he quickly lost his nerve. Norfolk was imprisoned in the [[Tower of London]] for nine months and only freed under house arrest when he confessed all and begged for mercy.{{sfn|Williams|1972|pp=101–02|ps=}} [[Pope Pius V]], in his 1570 [[papal bull]] ''[[Regnans in Excelsis]]'', excommunicated the Protestant Elizabeth and permitted all faithful Catholics to do all they could to depose her. The majority of English Catholics ignored the bull,{{sfn|Dures|1983|p=17|ps=}} but in response to it, Elizabeth became much harsher to Catholics and their sympathisers.{{sfn|Starkey|2001|p=322|ps=}}