Alan IV, Duke of Brittany of William the Bastard, Duke of Normandy (later to become known as William the Conqueror) support of rebels in Brittany against Alan's maternal uncle, Conan II. Conan II died in late 1066 during a campaign in Anjou, and was succeeded by Alan's parents, Conan's sister Hawise and her husband Hoel II. Hoel ruled as regent from Hawise's death in 1072 until Alan reached his majority in 1084. To prevent further hostilities during his invasion of England, William I married his daughter Constance to the new duke Alan in 1087. The marriage ceremonies may have taken place in Bayeux in Normandy.
Frederick William, Duke of Cieszyn "Baroness of Hohenstein" by Imperial order at Vienna on 8 May 1640. She married firstly with Tluck of Toschonowitz, marshal of the Cieszyn castle, and after his death, with Nicholas Rudzki. 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.