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
Stewart of Darnley both having claim to the English throne. The son of this union James VI of Scots succeeded to the throne of England as James I. The later English Kings of the House of Stuart, from James I and Charles I onwards, were more properly members of the Stewart of Darnley branch, and all drew upon their feudal heritage in Lennox. The Stewarts of Darnley were descended from Sir John Stewart of Bonkyll, the second son of Alexander Stewart, 4th High Steward of Scotland. Their name is derived from Derneley, a barony in Eastwood parish, Renfrewshire one & a half miles