Passage: These events led rapidly to Mary's defeat and imprisonment in Loch Leven Castle. The Scottish lords forced her to abdicate in favour of her son James VI, who had been born in June 1566. James was taken to Stirling Castle to be raised as a Protestant. Mary escaped from Loch Leven in 1568 but after another defeat fled across the border into England, where she had once been assured of support from Elizabeth. Elizabeth's first instinct was to restore her fellow monarch; but she and her council instead chose to play safe. Rather than risk returning Mary to Scotland with an English army or sending her to France and the Catholic enemies of England, they detained her in England, where she was imprisoned for the next nineteen years.

Question: Who assured support for Mary?
Elizabeth