Elizabeth I succeeded her half-sister
Mary I as queen of England in 1558. Elizabeth's accession was disputed due to the questioned legitimacy of the marriage of her parents (
Henry VIII and
Anne Boleyn), and Elizabeth's own questioned legitimacy due to the
Act of Succession 1536. Under Henry VIII and his advisor
Thomas Cromwell, power was gradually shifted from regional institutions to royal control. This course was encouraged by Elizabeth's counsellors such as
William Cecil and a policy of centralization was the approach favoured by Elizabeth herself at least in regards to the northern border region. Opponents of Elizabeth looked to
Mary, Queen of Scots, the descendant of Henry VIII's sister
Margaret. The claims were initially put forward by Mary's father-in-law, King
Henry II of France, and Mary upheld them after her return to Scotland in 1561. Many
English Catholics, then a significant portion of the population, supported Mary's claim as a way to restore Roman Catholicism. This position was especially strong in
Northern England, where several powerful nobles were Roman Catholics; there had been similar risings against Henry VIII; the
Pilgrimage of Grace of 1536 and
Bigod's Rebellion of 1537. Supporters of Mary hoped for aid from France (among Scots) and possibly Spain (among English). Mary's position was strengthened by the birth of her son,
James, in 1566 but weakened again when she was deposed in July 1567. Following this, she fled to England and at the time of the Rising was in the custody of the
Earl of Shrewsbury, on Elizabeth's orders. ==Rebellion under Northumberland and Westmorland==