Janet Kennedy is best known as the mistress of the King of Scotland who is generally regarded as the most successful of the Stewart monarchs of Scotland, but whose reign ended where?
Janet Kennedy:  She is best known as the mistress of King James IV of Scotland. James IV of Scotland:  He is generally regarded as the most successful of the Stewart monarchs of Scotland, but his reign ended in a disastrous defeat at the Battle of Flodden, where he became the last monarch not only from Scotland, but from all of Great Britain, to be killed in battle.
Battle of Flodden