"William de Salisbury, 1st s. and h. ap., fought for the Empress Maud at the siege of Winchester in 1141, but was captured by the Earl of Hertford when her forces were routed in Sep. In 1142 and 1143 he was in charge of Salisbury for the Empress, presumably acting as sheriff and constable of the castle. On 1 July 1143 he took part in the Earl of Gloucester's attack on Wilton Nunnery; and he d. after long suffering. It is not known if he were married, but he d. s.p." [1]
[1] George E. Cokayne and Geoffrey H White, ed., The Complete Peerage, rev., Vol. 11, Rickerton to Sisonby (London: St Catherine Press, 1949), 375, includes citations in footnotes.