Modern Stewart Royal Medium Weight Tartan. The Royal Stewart tartan generally referred to simply as the Royal Tartan, has been associated with the Royal House of Stewart for several centuries. The Stewart monarchs were descended from Walter, High Steward of Scotland, who married Princess Marjory, daughter of King Robert the Bruce. Their son, King Robert II, was the first Stewart king. The male line of the Royal House of Stewart ended with the death of Prince Henry, brother of Prince Charles Edward. H.M. The Queen is chief of the Royal House of Stuart and “chief of chiefs”.