William Fiennes, 1st Viscount Saye and Sele (28 June 1582 14 April 1662) was born at the family home of Broughton Castle near Banbury, in Oxfordshire. He was the only son of Richard Fiennes, seventh Baron Saye and Sele. He was descended from James Fiennes, 1st Baron Saye and Sele, who was Lord Chamberlain and Lord Treasurer under Henry VI and who was beheaded by the rebels under Jack Cade on 4 July 1450.Fiennes, like many of his family, was educated at New College, Oxford. He was a descendant and heir of the sister of William of Wykeham, the college's founder. He married Elizabeth, daughter of John Temple of Stowe, in 1600. He succeeded to his father's barony in 1613, and in parliament opposed the policy of James I, undergoing a brief imprisonment for objecting to a benevolence in 1622.