Sir Willam Stanley, Baronet, (1548—1630) son of Sir Rowland Stanley bt of Hooton (?-1612), was a member of the famous Stanley family. He married Anne Dutton, a bride of ten, but the marriage was dissolved in 1565. He served under his kinsman Edward Stanley, 3rd Earl of Derby (c.1508-1572).

He was brought up a Roman Catholic. He had fought on the Spanish side in the Netherlands under the Duke of Alva from 1567 to 1570, and then served the English crown in Ireland. Throughout the period of his service in Ireland, he had fought with distinction, despite being a co-religionist of his antagonists. When in 1585 he was sent to the Netherlands, his loyalty to the crown was on the one hand apparently unquestioned, but on the other there had been rumours of links with Jesuit priests and connections with the Babington plot. With hindsight, therefore, it was a mistake to have put him in command of the recently acquired city of Deventer with an army of Irish Roman Catholics. Despite Leicester having defended his loyalty to the suspicious Dutch, Stanley betrayed the town to the Spanish, the day after Zutphen had similarly been betrayed by the English commander Rowland York (January 28).

Shortly after the event, Cardinal William Allen wrote a pamphlet defending Stanley's actions with a view to justifying the assassination of Elizabeth I as provided for in the bull Regnans in Excelsis.

Richard Barnfield dedicated Cynthia to Stanley in 1595.