Mary Henrietta, Princess Royal and Princess of Orange. Born on 4th November 1631 at St. James's Palace, she was the eldest daughter of Charles I and Henrietta Maria of France. She was the first holder of the "Princess Royal" title, which came into being because her mother wanted her daughter to have a title similar to her title of "Madame Royale" in France. She married William II, Prince of Orange and was the mother of the future William III of England. Mary died of Smallpox aged 29 in 1660.
CDV of 1865 Easter mass at St. Peter's. Click on image for 19th century interp. that the Papal troops are gathered for victory. Larger format on Wiki, https://commons.wikimedia.org/wiki/File:Ostermesse_auf_dem_Petersplatz_Rom.jpg