John Arundell (1576 – December 1654), Esquire, of Trerice in Cornwall, later given the epithet "Jack for the King", was a member of an ancient Cornish gentry family, who as a Royalist during the Civil War served King Charles I as Governor of Pendennis Castle, Falmouth. In 1646 he retained the castle in a heroic manner during a five-month-long siege by Fairfax, during which his forces were reduced by hunger to eating their horses, and finally achieved an honourable surrender