For a cadet, even of such a family as the Berkeleys, Sir John had a successful and active career, stretching over 50 years. Yet he appears to have taken little part in the political upheavals or military conflicts of his time. There is no hint that he was ever anything more than a comfortably established landowner and a hard working local officer of the Crown.
John’s father, nicknamed ‘Thomas the Ritch’ by the Berkeley’s biographer John Smyth, had the unhappy distinction of being the custodian of the deposed Edward II at Berkeley castle. It was his eldest son by his first marriage, John’s half-brother Maurice, who succeeded to the barony when Lord Berkeley died in 1361. John himself was the youngest of the four sons born to Lord Berkeley by his second wife, but the others died young leaving him as heir to a substantial part of his father’s estates and as the sole heir to those of his mother. He was born at Wotton-under-Edge, where his mother afterwards founded a grammar school, and one of his godparents was the prior of Bath. Smyth found cause for criticism of ‘the great indulgence of this Lord Thomas his father ... and the powerfull working of his mother’ who by various settlements made in 1352, when John was no more than a baby, arranged for his inheritance of the Berkeley manors of Beverstone, Tockington, Over, Compton Greenfield, King’s Weston, Woodmancote and Syde in Gloucestershire, ‘Cernecote’, Chelworth, ‘Caldecote’ and ‘Bere Revell’ in Wiltshire, and Barrow Gurney and half of Sock Dennis in Somerset, along with many other lands and advowsons in those counties as well as in Devon and Dorset. Thus, says Smyth, was a ‘great morsell cut out from the heirs of this noble family’. It was perhaps for this reason that in 1383 John requested an exemplification from Chancery of certain transactions relating to the Berkeley estates. After his father’s death he remained for several years a minor in the King’s wardship, and, in any case, certain of his manors were not to pass to him until the death of his mother in March 1386. His inheritance from her included the manor and advowson of Clevelode in Worcestershire and the manors of Low Ham, ‘Hamburceys’ near Langport and a quarter of that of Exton in Somerset.
Berkeley’s first marriage, to the daughter of Sir Robert Assheton (treasurer of England 1375-7), resulted in no permanent material advantage, even though his father-in-law had arranged that Berkeley and his wife Eleanor and their children should have three Somerset manors after his death, for Eleanor predeceased her father and the marriage was apparently childless. It was his second marriage that most handsomely increased his fortune. On the death of John Bettesthorne in February 1399 Berkeley acquired in right of his wife Elizabeth, Bettesthorne’s only daughter, a considerable amount of land in Dorset, Wiltshire and Hampshire, centred on an estate in the New Forest. When the subsidy of 1404 was collected Berkeley was said to be able to spend more than 500 marks a year (£333 6s.8d.). The estimates of 1412 were similarly high: Berkeley’s Gloucestershire lands were then said to be worth £157 a year, those in Somerset £68 a year, those in Wiltshire £67 13s.8d. a year and those in Hampshire £40 13s.4d. a year. An income of over £333 from his estates — and this does not include his properties in Dorset and Worcestershire — indicates a man of considerable wealth. Indeed, as John Smyth pointed out, the Berkeleys of Beverstone and Bisterne, of whom John was the ‘stock-father ... long flourished in great eminency with opulent possessions, little inferior to this noble family of the Berkeleys of Berkeley castle’.
Certainly, John and Elizabeth were quick to express their gratitude for the Bettesthorne inheritance: in November 1399 they obtained a royal licence to augment a chantry of one chaplain in the parish church of Mere, Wiltshire, of which they were now patrons, by establishing two other chaplains who were to pray for them and for the soul of Elizabeth’s father who was buried there. Lands in Mere and in Clapton (Somerset) were given for the chaplains’ support, and the Berkeleys also granted lands in Gillingham and Milton in Dorset to the chantry of St. Katherine in Gillingham parish church. Further, in February 1410, they and John Prophet, rector of their local church at Ringwood and at that time keeper of the privy seal, obtained a licence to found a chantry in St. Mary’s chapel on their manor of Bisterne, and land in that manor and in Poulner nearby was made over to the chaplain, who was not only to pray for the founders and John Bettesthorne but also to administer to the people of the hamlet.
There is no positive evidence that Berkeley ever served abroad in a military capacity.
Berkeley, having made his will on 21 Feb. 1428, died on 5 Mar. following, at the age of 76. He wished to be buried in St. Mary’s chapel at Mere and left to the chapel vestments embroidered with gold leopards and swans, an ivory tablet, an ‘Apokalipse’ and vessels to contain the Holy Sacrament. He left bequests totalling £14 10s. to the cathedrals of Canterbury, Worcester, Wells, Exeter, Winchester and Salisbury, to Kingswood abbey, to various churches on his estates and to the friars of Bristol and Gloucester. A missal and vestments were left to the priories of Christchurch (Twynham) and Minchen Buckland. His servants were to share £15, and his poor tenants 20 marks. Berkeley’s widow Margaret, his third wife whom he had married only a short while before, was to have his movable goods and £20, and his son and heir, Sir Maurice Berkeley, was to have a further £20. Altogether the monetary bequests in the will amounted to £110 10s. Berkeley’s executors included Master Oliver Dingley, a canon of Salisbury, and the supervisors of the will were the prior of Christchurch and the husband of Berkeley’s daughter Eleanor, Sir Richard Poynings, son and heir-apparent of Robert, Lord Poynings. Berkeley’s children had all married well: before her marriage to Poynings Eleanor had been the wife of John Arundel, Lord Mautravers (de jure earl of Arundel), and after her father’s death she was to marry Sir Walter (by then Lord) Hungerford; the heir, Maurice, had married Laura, daughter of Henry, Lord Fitzhugh; Elizabeth had married, first, Edward, Lord Charleton of Powis and then John Sutton, Lord Dudley; and Joan had married a substantial Somerset landowner, Sir Thomas Stawell. Berkeley’s widow survived him by 16 years.