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 of marriage were called in the parish of Canongate. A proclamation was made at the Cross of Edinburgh on 28 July that government would be in the joint names of the king and queen of Scots, thus giving Darnley equality with, and precedence over, Mary. This was confirmed in the circulation of a silver ryal in the names of Henry and Mary. On 29 July 1565, the marriage took place by Roman Catholic rites in Mary's private chapel at Holyrood, but Darnley (whose religious beliefs were unfixed – he was raised as a Catholic, but was later influenced by Protestantism)