Lady Jane Grey was the eldest child of Lord Henry and Lady Frances Grey, the duke and duchess of Suffolk. She was a viable heir to the English throne because of her maternal grandmother, Princess Mary Tudor. After the death of her first husband, King Louis XII of France in 1515, Mary secretly wed her true love, Charles Brandon. Brandon was her brother Henry VIIIs best friend; the kings friendship and Brandons service to the Crown led to his creation as duke of Suffolk in 1514. He and Mary had a son, Henry, who died as teenager. Their next eldest child was a daughter, Frances. Under the terms of the Third Act of Succession 1544 and Henry VIIIs last will and testament 1547, the Suffolk line would inherit the throne after Henry VIIIs children died childless. In other words, the throne would pass to Henrys son Edward; if Edward died childless, it passed to Henrys eldest daughter Mary; if she died childless, it passed to Henrys youngest daughter Elizabeth. If Elizabeth died childless, the throne passed to Lady Frances. This plan completely disregarded the children of Henrys elder sister Margaret, the former queen of Scots. Henry did not care for Margaret and, more importantly, did not want the English throne in Scottish hands.

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