William FitzWilliam (Lord Deputy) William FitzWilliam (Lord Deputy) Sir William FitzWilliam (1526–1599) was an English Lord Justice of Ireland and afterwards Lord Deputy of Ireland. In 1587, as Governor of Fotheringhay Castle, he supervised the execution of the death sentence on Mary, Queen of Scots. He was the Member of Parliament for Peterborough and represented County Carlow in the Irish House of Commons. He lived at Gainspark, Essex, and Milton Hall. FitzWilliam was born at Milton Hall, Northamptonshire, the eldest son of Sir William (d. 1576) and grandson of William Fitzwilliam, Sheriff of London, who had been treasurer and chamberlain to Cardinal Wolsey and
Mary, Queen of Scots She was moved to Fotheringhay Castle in a four-day journey ending on 25 September, and in October was put on trial for treason under the Act for the Queen's Safety before a court of 36 noblemen, including Cecil, Shrewsbury, and Walsingham. Spirited in her defence, Mary denied the charges. She told her triers, "Look to your consciences and remember that the theatre of the whole world is wider than the kingdom of England". She protested that she had been denied the opportunity to review the evidence, that her papers had been removed from her, that she was denied access to