Sir John Greyndore was a notable soldier and an important figure in the government of the southern Welsh marches. His lands were all on the Gloucestershire-Monmouthshire border, in or near the Forest of Dean. From his father he inherited the manor of Clearwell, Gloucestershire, and lands at English Bicknor, Newland and St. Briavels, in the same county, and at Hadnock, near Monmouth. From his mother (after her death in 1375 and that of her second husband in the following year) he received the manor of Abenhall and land at nearby Little Dean, and in the course of his career he also acquired half the manor of Micheldean. His first wife, Marion Hathewey, likewise came of a local family, with land at Ruardean.
John is first mentioned in September 1376 when (aged about 20) he entered into a joint recognizance with his relation, Raulyn Greyndore of Micheldean. Three years later he served for the first time as a royal tax collector. In 1394 he accompanied Richard II to Ireland, and by April 1398 he had been knighted. During Richard II’s reign he also served several local magnates: in 1384 Guy, Lord Bryan, had made him constable of his castle of St. Briavels and keeper of the Forest of Dean during Guy’s lifetime, and a year later this appointment was confirmed by the King for Greyndore’s own life. He was also retained by Gilbert, Lord Talbot, who before his death in 1387 granted him a life annuity of £10 from the lordships of Archenfield and Goodrich in Herefordshire. In addition, he had links with William Beauchamp, Lord Abergavenny, for whose Kentish lands he was to act as a feoffee in 1400. Several members of the Greyndore family (including Sir John’s father) had been retainers of John of Gaunt, duke of Lancaster, and Sir John himself may also have served the duke, to whom he conveyed land in Hadnock in 1392.
Such a connexion would explain Greyndore’s rise to prominence after the accession of Henry IV. As early in the reign as 12 Oct. 1399, by which time he was already described as a King’s knight, he was granted custody of the Gloucestershire lands (worth 20 marks a year) of the late William Blount, with the marriage of his heir, Isabel. Furthermore, three months later he was appointed sheriff of Glamorgan, which formerly hereditary office had been confiscated following the treason of Thomas, Lord Despenser. Between September and December 1400, he took part in Henry IV’s Scottish campaign, serving with Lord Grey of Codnor at Roxburgh and with the prince of Wales at Leith. In January 1401 he was first returned to Parliament, and in August following he was summoned to a great council at Westminster.
By now Sir John was attached to the household of Prince Henry, the King’s lieutenant in Wales, and on 21 July 1403 (with a company of five men-at-arms and 40 archers) he fought in the prince’s retinue at the battle of Shrewsbury. At other times during the period from April 1403 until July 1404 he was paid the wages of his own large retinue of 20 lances and 100 archers, operating near Montgomery and elsewhere in Wales. Then, in October following, he found time to attend the ‘Unlearned’ Parliament at Coventry, the other representative for Herefordshire being his neighbour, Thomas Walwyn II of Much Marcle, to whom he was to be later connected by marriage when his daughter, Joan, married Walwyn’s son, William. By February 1405 Greyndore had exchanged his command at Radnor for the posts of deputy constable of the castle and town of Monmouth and of Skenfrith castle. During the following spring he played a major part in two signal defeats inflicted on the Welsh in that area. The first was on 11 Mar., when 8,000 rebels from Gwent and Glamorgan attacked and burnt the town of Grosmont. Prince Henry counter-attacked with ‘mon petit meigne de mon hostel’ under Gilbert, Lord Talbot, who was joined by the retinues of Sir William Newport and Greyndore. Although these forces ‘ne feurent q’un tres petit povoir en tous’, they routed the Welsh, and killed, it was said, nearly a thousand of them. Not long afterwards Greyndore and Lord Grey of Codnor were in command of the garrison of Usk castle when (perhaps on 5 May) it was attacked by a Welsh force under Griffith, eldest son of Owen Glendower. The English sallied out and defeated the rebels on the hill of Pwll Melyn, capturing Griffith and killing his uncle, Tudor. After the battle, 300 Welsh captives were executed.
Sir John’s military services continued to be much in demand. In June 1405 he was appointed constable of Chepstow, with responsibility for the surrounding area, and in the following September he was negotiating for the submission of the defeated rebels of Gwent. In March 1406 he was granted (probably as a reward) the stewardship of the Mortimer lordships of Usk and Caerleon, and in May following (when he had an episcopal licence to appoint his own confessor) he became constable of Whitecastle, an appointment for life. Nor did his services go unrecognized by Parliament, for on 19 June Sir John Tiptoft, then Speaker, made specific reference to him as one of those whom the Commons were petitioning the King to reward for their ‘grandes labours et disseases pur resister les rebealx de Gales’. Exactly what rewards came his way as a result is unknown, but on 22 May 1408 he had a life grant of lands in the lordship of Newport, worth 40 marks a year, confiscated from various Welsh rebels.
Meanwhile, during the summer of 1407, Sir John had been with Prince Henry at the siege of Aberystwyth castle, and he witnessed the articles of surrender drawn up there on 8 Sept. Glendower repudiated the agreement, however, and the castle held out for another year. Prince Henry’s trust in Greyndore is amply demonstrated by the fact that he was immediately appointed constable of this key fortress, and he apparently retained command until 1410, by which time the long rebellion had been effectively crushed. Not long before, a barge of his (operating from Bristol) had been involved in capturing and plundering a Genoese carrack at Milford Haven. Greyndore’s men carried off 60 butts of wine ‘for safe-keeping’ at Chepstow, but in March 1410 Sir John was ordered to return them.
Shortly after Henry of Monmouth’s succession to the throne, Greyndore was appointed steward and constable of Monmouth and the Three Castles (Grosmont, Skenfrith and Whitecastle) and granted a life annuity of £64 over and above his wages. He thus became the principal officer of the duchy of Lancaster in south-east Wales, as well as a member of the duchy council; and it was as such that he served ex officio on royal commissions and as a justice itinerant.
On 16 June 1415 Sir John was granted wide powers of government in the southern Welsh march, it being his duty to keep the peace there during Henry V’s absence in France. This commission seems to have been a dead letter, however, for four days earlier he had been granted royal letters of protection as a member of the King’s army himself and, though aged about 60, he served at the siege of Harfleur with ten men-at-arms, 30 archers and 120 miners, the latter presumably from the pits in the Forest of Dean.