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
Tutbury Castle Gaunt. Her court lavishly patronised music and the arts, and was said to have "somewhat similar to a modern Windsor" in its ambition. In June 1568, Mary, Queen of Scots was at Carlisle Castle after fleeing from Scotland after her defeat at the battle of Langside, and the English Privy Council decided to lodge her either at Nottingham Castle, Fotheringhay Castle or Tutbury, so that she was further from the Scottish border or Yorkshire. In January 1569 the Scottish Queen was taken from Bolton Castle, going first to Ripon and staying a night nearby, then to Wetherby staying a night