Henry Stuart, Lord Darnley not together in early 1545 and a letter of March 1566, from Mary Queen of Scots, indicates Darnley was then nineteen years old. Therefore the date 1546 would seem probable. A descendant of both James II of Scotland and Henry VII of England, Henry Stuart, Lord Darnley, was heir to two royal houses, the House of Stuart and the House of Tudor, thus he had claim to both the Scottish and English thrones, a claim that may have cost him his life. In 1545, his father, Matthew Stewart, 4th Earl of Lennox was found guilty of treason in Scotland for
Henry Stuart, Lord Darnley the Spanish Ambassador in Paris heard this news, the headlines were that Darnley "had murdered his wife, admitted the exiled heretics, and seized the kingdom." However, on 20 March, Darnley posted a declaration denying all knowledge of or complicity in the Rizzio murder. Mary no longer trusted her husband, and he was disgraced by the kingdom. On 27 March, the Earl of Morton and Lord Ruthven, who were both present at Rizzio's murder and had fled to England, wrote to Cecil claiming that Darnley had initiated the murder plot and recruited them, because of his "heich quarrel" and "deadly hatred"