Sir William Knyvett, (also spelt Knyvet), often called John, was born, married and died at Buckenham Castle, Norfolk. He wed Joan c1477. She was born c1442, and died c1484.

Sir William and his father, Sir John, fought for Edward IV, to be, under Richard Neville, Earl of Warwick. His mother singly warded off those who sought to take over the castle at Buckenham while they were away fighting. They also backed the Earl of Warwick in his takeover for Henry VI in 1470/71, but they were pardoned by Edward IV.

His royal service began at his majority in port customs and as Justice of the Peace for over half a century and he was twice appointed Sheriff of Norfolk.He was knighted in 1475 and continued to hold important posts throughout his life. Several years before his death, he was a member of peace commissions with the highest peers of the land.

Sir William took part in the abortive rising of Henry, 2ndDuke of Buckingham in 1483 against Richard III and in favour of Henry Tudor. He was able to rescue the child Edward, 3rd Duke of Buckingham to be, but he lost Buckenham and was attained for the rest of this brief reign. After the battle of Bosworth in August 1485, Sir William petitioned Henry VII in parliament for reversal of the attainer and the return of his properties. This was granted.

He is believed to have fought, on the king's side, at The Battle of Stoke, June 16, 1487.

Sir William was witness to the Papal dispensation for Elizabeth of York and her marriage to Henry VII. He was high on the list of personages attending royal functions but Henry's close purse and his policy regarding noble claimants and their retainers prevented the award of a peerage.

The close association of Sir William with the Dukes of Buckingham by marriage to Joan Stafford lead to his appointment as Councillor and Chancellor to Edward 3rd Duke of Buckingham at Penshurst and London.

National Archives (UK)
Reference: KNY 12 369 x 2
Statement of the tithe of Sir William Knyvett and William Fitzwilliam to the manor of Hethersett. Deriving it from Jane wife of Sir Robert Tateshale, (late 15th century).

Reference: HIL/1/54,870X1
Grant by George Nevyll knight Lord Burgevenny, son of Margaret wife of George Nevyll, Lord Burgevenny, daughter of Hugh at Fenne, to William Knyvet knight of 100a. of land and liberty of fold formerly John Stede's, (December 1, 1494).

Reference: HIL/1/55,870X1
Appointment by William Knyvet of Edmund, his son, to receive seisin of same property from Godfrey Toppes and others Nevyll's attornies, (December 20, 1494).

Reference: KIM 2M/9
Conveyance by Robert Wyngefeld, Kt., and his wife Ann, William Berdwell, senior, Edmund Bokenham, Esqs., John Paynot and Laurence Gerard, clerks, to George, Duke of Clarence, John, Duke of Norfolk, Antony Wodevyle, lord of Scales, John Wyngefeld, Kt., William Knyvet and William Brandon, Esqs., and Geoffrey Robyns, Manor of Barnham Broom, land in Barnham Broom, Colton and Bixton, 7 Edward IV, (April 9, 1467).

Reference: KIM 2Q/17
Appointment by Robert Wyngefeld, Kt., and Ann, his wife, William Bardwell, senior, Edmund Bokenham, Esq., John Paynot and Laurence Gerard, clerk, of Peter Glamorgan and John Bryvile as their attorneys to deliver to George, Duke of Clarence, John, Duke of Norfolk, Antony Wodevyle, lord of Scales, John Wyngefeld, Kt., William Knyvet, William Brandon and Geoffrey Robyne, full and peaceful seisin and possession of the manor of Barnham Broom, 7 Edward IV, (April 9, 1467).

Reference: KNY 426 371 x 9
Copy of inquisition post mortem of Sir William Knyvett, inc. copy of will, (1516)