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 of 7 February 1587, Mary was told that she was to be executed the next morning. She spent the last hours of her life in prayer, distributing her belongings to her household, and writing her will and a letter to the King of France. The scaffold that was erected in the Great Hall was draped in black cloth. It was reached by two or three steps and furnished with the block, a cushion for her to kneel on and three stools, for her and the earls of Shrewsbury and Kent, who were there to witness the execution. The executioners (one