29 July 1565 – Mary, Queen of Scots marries her cousin, Henry Stuart – Lord Darnley.
Henry Stuart was the son of Margaret Douglas and her husband Henry Stuart. Margaret Douglas was the daughter of Margaret Tudor (dowager Queen of Scotland) and Archibald Douglas.
Marie Stuart (Mary, Queen of Scots) was the daughter of Marie de Guise and James V of Scotland. James V was the son of Margaret Tudor and James IV.
Mary and Henry were first cousins.
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