Empress Matilda was the king of England's daughter.
Empress Matilda . The daughter of King Henry I of England , she moved to Germany as a child when she married the future Holy Roman Emperor Henry V . Henry I ( c. 1068 -- 1 December 1135 ) , also known as Henry Beauclerc , was King of England from 1100 to his death . In the Rout of Winchester ( 14 September 1141 ) the army of imprisoned King Stephen of England , led by his wife , Queen Matilda of Boulogne , Stephen 's brother Bishop Henry of Blois , and William of Ypres , faced the army of Stephen 's cousin Empress Matilda , whose forces were commanded by her half-brother Earl Robert of Gloucester .