Territorial evolution of France face up to the formidable challenge with which they were presented. The Duke of Normandy William the Conqueror became King of England in 1066 through his victory at Hastings over the Saxons. On the extinction of his male line of descent, his heir was the Duke of Anjou, Henry Plantagenet, grandson by his mother of Henry I of England. Two months before he ascended to the English throne, as Henry II, he married Eleanor, Duchess of Aquitaine, the richest heiress in the French kingdom and ex-wife of the King of France. The kings of France nevertheless, held some trump cards:
Frederick William, Duke of Cieszyn Frederick William, Duke of Cieszyn Frederick William of Cieszyn (, , ; 9 November 1601 – 19 August 1625) was a Duke of Cieszyn since 1617 until his death. He was the third but only surviving son of Adam Wenceslaus, Duke of Cieszyn, by his wife Elisabeth, daughter of Gotthard Kettler, Duke of Courland. His mother died from childbirth complications ten days after his birth, on 19 November 1602. Since his early years, Frederick William's education was entrusted to the Silesian humanist Baltzar Exner. In 1611 Duke Adam Wenceslaus decided to convert to the Catholicism, and all the Protestant members