"William of Winchester (11 April 1184 – 13 December 1213), also called in English William of Lunenburg (German: Wilhelm von Lüneburg) or William Longsword, a member of the House of Welf, was heir to his family´s allodial lands in the Duchy of Saxony after the deposition of his father, Duke Henry the Lion in 1180.
William was the fifth and youngest son of Henry the Lion and Matilda, the eldest daughter of King Henry II of England. He was born in Winchester, England during his father´s exile; he probably remained there when Henry returned to Saxony and was raised at King Richard´s court." - (en.wikipedia.org 17.10.2020)
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