“After he dropped the royal standard in a Welsh ambush during Henry II's campaign into Wales of 1157, however, his political importance waned. As royal constable, his office required that he hold the standard to indicate the king's position during any military engagement. Dropping the standard seemed to signal the king's death. At the royal court held at Easter, 1163, Henry was accused of treason for that act by a claimant to the Montfort estate. The two men fought a judicial duel a few months later. Jocelin details Henry's judicial dual with Robert de Montfort (a rival for Henry's wife's inheritance) on Fry's Island in the River Thames at Reading. Henry's body was carried senseless from the site of the duel by monks of the nearby Reading Abbey, but he survived and took the Benedictine cowl. As a convicted traitor, however, his estates and offices were forfeit, and his family was disgraced. He was allowed to remain as a monk at Reading Abbey, where he remained for the rest of his life.”1315

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