Historians in the 16th and 17th centuries focused on Edward's relationship with Gaveston, drawing comparisons between Edward's reign and the events surrounding the relationship of Jean Louis de Nogaret de La Valette, Duke of Épernon, and Henry III of France, and between George Villiers, 1st Duke of Buckingham, and Charles I of England. In the first half of the 19th century, popular historians such as Charles Dickens and Charles Knight popularised Edward's life with the Victorian public, focusing on the king's relationship with his favourites and, increasingly, alluding to his possible homosexuality. From the 1870s onwards, however, open academic discussion of Edward's sexuality was circumscribed by changing English values. By the start of the 20th century, English schools were being advised by the government to avoid overt discussion of Edward's personal relationships in history lessons. Views on his sexuality have continued to develop over the years.