John Bayntun was born in December 1407 at Faulston House, in the County of Wiltshire. He was most likely known as John de Benton or Baynton, however we see the spelling of the surname changing to Bayntun around the beginning of the 17th century.

He married his first cousin, once removed, Joan Dudley, who was the daughter of Sir Richard Dudley and his wife Elizabeth de Beauchamp and the granddaughter of Sir John de la Roche and his wife Wilhelma de la Mare.

When Sir John de la Roche, died on the 30th September 1400, his property was divided between his co-heiresses (his daughters), but some of these manors were held in dower by his widow until her death on the 31st October 1410. In her will, executed in 1411, a great deal of de la Roche and de la Mare property was conveyed to her grandson, John Bayntun. Wilhelma was the heiress of her father, Robert de la Mare, and a lot of this land was also settled on her grandson.

Because John was just 4 years old at the time, an agreement was drawn up, with Wilhelma giving control of the manors to her eldest daughter, Elizabeth and her husband, Sir Walter de Beauchamp, until such time as John Bayntun became of age.

The following is the wording of this Indenture, dated 1411:
Indenture between Walter de Beauchamp, Knight, party of the first part, and John Baynton, gentleman, party of the second part. Since a controversy has arisen between the aforesaid Walter and his wife Elizabeth, one of the daughters and heirs of John de la Roche, Knight, and his wife Wilhelma, and John Baynton, his kinsman and another heir of the said John and Wilhelma de la Roche, viz., the son of Joan, the daughter of the aforesaid John and Wilhelma, concerning about a certain bequest between the aforesaid Walter and John in the Chancellery of our Lord King Henry IV in the twelfth year of his reign (1411), both about certain lands of the said John de la Roche and about other lands which belonged to the aforesaid Wilhelma, his wife, concerning which lands the aforesaid Wilhelma [lately died 1410] and concerning the right and title and interest in the Manor of Chyreton (Cherington) in the county of Gloucester and the Manors of Leventon (Lavington) and Chawe (Shaw) in the county of Wiltshire and the Manors of Haun, Preston, and Tarrant Gundeville in the county of Dorset. Given 6 Henry VI.

Wilhelma's last Will and Testament named her son-in-law, Sir Walter de Beauchamp, as overseer of the administration of her estate, probate being allowed in the Prerogative Court of Canterbury on the 21st November 1410.

Sir Walter was married to Elizabeth de la Roche, the sister of John's mother, Joan de la Roche and he and his wife were therefore entrusted with the wardship of lands specifically bequeathed to Wilhelma's grandson, John, for which custody he undertook to pay annually into the Royal Escheator the sum of 80 Marks until John Bayntun reached the age of 21.

But by December 1428 John had become of age and was in possession of the following manors:

THE MANOR OF LAVINGTON
The half manor held by Peter de la Mare circa 1166 is that which came to be called first LAVINGTON BAYNTON and later LAVINGTON DAUNTSEY. It passed from Peter down through the generations to Wilhelma de la Mare, the wife of Sir John de la Roche of Bromham, and in her will, she conveyed the manor in 1410 to her daughter Elizabeth, wife of Sir Walter de Beauchamp. From Elizabeth and Walter the manor descended like that of Whaddon to John Baynton. In 1541, after the dissolution of the house of Bonhommes at Edington, the manor which had descended from the Rochelles to Edington was granted to Sir Edward Bayntun, the great-great-grandson of Sir John, and thenceforth the two manors, distinguished by the names of Lavington Baynton or Dauntsey and Lavington Rector, descended together.

THE MANOR OF CHERINGTON
The Manor of Cherington was in the possession of Robert de la Mare in 1201 and descended, along with others, to Wilhelma de la Mare. In the terms of her will she gave control of this manor to her daughter, Elizabeth and upon the death of Lord Saint Amand it descended to John Bayntun.

THE MANOR OF SHAW
Shaw, in the parish of Melksham, was held in 1400 by Sir John de la Roche and after his death it was held in dower by his relict, Wilhelma de la Mare, until her death. From that date it was held in trust by Elizabeth de Beauchamp until John came of age.

THE MANOR OF LOWER HEYFORD
Lower Heyford was situated in Oxfordshire and was conveyed to Peter de la Mare in 1330 and it descended, along with other de la Mare lands, through Wilhelma de la Mare to John Bayntun. It remained Bayntun property until 1533 when John's son, Sir Edward Bayntun, sold it to Corpus Christi College, Oxford for £709.

THE MANOR OF TOLLARD LUCY
In 1392 Sir John de la Roche was in possession of Tollard Lucy until his death in 1400. From then it passed to his wife, Wilhelma and in 1428 to John Bayntun.

THE MANOR OF HAUN

THE MANOR OF MARSH BALDON
John Bayntun was returned as holding lands in Marsh Baldon which was first owned by Robert de la Mare before 1173 and had descended in this family to John's grandmother, Wilhelma de la Mare, and from her to John.

THE MANOR OF DELAMERES OR LAMBERDES
Delameres or Lamberdes was a small manor and may have represented lands in Minchinhampton in which Malmesbury Abbey claimed the rights to in c1234, although it was in the hands of Robert de la Mare in 1259. This was another manor that was passed onto John by Wilhelma de la Mare.

NEBELS ESTATE AND FARM
Nebels Estate and Farm were in the possession of Robert de la Mare in 1250 and, like the others, were inherited by John Bayntun. But a document shows Nebels Farm in the hands of Sir Henry Long some time before 1556 - which indicates it was most likely sold by Sir Andrew Bayntun (1515-1564).

THE MANOR OF PRESTON
in the County of Dorset.

THE MANOR OF TARRANT GUNDEVILLE
in the County of Dorset.

THE MANOR OF FAULSTON
The family Manor of Faulston was conveyed to John Bayntun by his mother when she was married for the second time to William Whaplode.

Sir John Bayntun was Sheriff of Wiltshire in 1429-30 and again in 1443-44. He was knighted in 1434 and until his death, was a member of a long series of offices in the county, as well as being a Member of Parliament for Wiltshire County in 1445 and 1446. The office of High Sheriff is of great antiquity, dating back to Saxon times. It is the oldest secular office in England and Wales, after the Crown.

It is not clear in what year Sir John Bayntun died but a collection of deeds transcribed in the 17th century, show him living at Faulston on the 14th July, 25 Henry VI (1447) as a Distributor of an Allowance on a Tax in Wiltshire.

There is no record of the burial place of Sir John, but it is thought he and his family before him, may have been buried in a square field, known as Chapel Close, which might have been either the site of a Chapel or a field attached to the Chapel which was next to Faulston House. There are no visible signs of any graves today, unless buried beneath the ground.

When Sir John Bayntun died he was succeeded by his son and heir John Bayntun