Complex sentence: Charles named as his successor his 16-year-old grand-nephew, Philip, Duke of Anjou grandson of Charles' half-sister Maria Theresa of Spain, the first wife of Louis XIV.
Split into simpler sentences: Charles named as his successor his 16-year-old grand-nephew, Philip, Duke of Anjou. He was the grandson of Charles' half-sister Maria Theresa of Spain, the first wife of Louis XIV.