From his maternal grandfather, Gilbert Berwick (d.1361), Roches inherited a share in the manors of Winterslow, Berwick and Worston, along with property elsewhere in Wiltshire, the first coming into his possession by November 1361 under the terms of an entail. Late in 1373 he succeeded to his father’s lands at Bromham (where the family had lived since the 13th century). To these estates, he added substantially in the course of his career: in 1376 he obtained the reversion of Draycot Fitz Payne, and three years later those of Shaw by Melksham, Horton and Chittoe, while in 1381 he acquired the manor of Huish, which he entailed in the male line. In Dorset he purchased moieties of the manors of Long Crichel and Hampreston along with property in Wareham, Wimborne Minster and Canford. Through his marriage to the daughter of Sir Robert de la Mare (d.1382), an important official in the earldom and duchy of Lancaster and executor of the will of Henry of Grosmont, Roches stood to obtain substantial holdings in Gloucestershire, Hertfordshire and Oxfordshire, but in fact these remained in the possession of his mother-in-law until after his death.
Roches’s father had long been retained by Queen Philippa, who in 1336 had appointed him as bailiff and chief mounted forester of Chippenham, Melksham and Pewsham for term of her life. John senior’s many royal commissions involving the queen’s interests point to the importance of this connexion, which was continued by our MP. On 31 Oct. 1361 the queen leased to the latter the manor of Woodrow in Melksham to hold for ten years (various subsequent grants by the Crown were to keep him in possession until 1390), and when his father died he succeeded him in his posts in the forest administration.
Roches’s services to Richard II began soon after the latter’s accession. On 20 Sept. 1377 he indented to serve at sea with a company of 50 men-at-arms and 50 archers in the retinue of the King’s uncle, Thomas of Woodstock, earl of Buckingham. They sailed from Bristol on 23 Oct., but although his men returned home on 25 Jan. following, Roches himself had by then already left them to go on to Bordeaux, landing there on the 11th. In the previous October he had been appointed as an ambassador to the Aragonese court for discussions with Peter III. Officially, his task was to notify the king about Richard II’s coronation, but he also carried full powers to negotiate an alliance. Now, at Bordeaux, he was joined by a Gascon clerk, Gerald de Menta, an expert on Aragonese affairs, and both men then set off for Barcelona, where Roches remained until March. He reached England again on 4 May, bringing with him a draft treaty for the approval of the young King and his uncle, John of Gaunt, and almost immediately he was ordered to go back to Barcelona to complete the negotiations. This time, he was to travel with the new lieutenant of Aquitaine, John, Lord Neville, but being unable to leave Plymouth for several weeks because of adverse weather, they did not arrive in Gascony until September, when their attention was taken up by the need to strengthen the defences of the duchy itself. Roches never finished his journey to Aragon, but he may have gone on an embassy to Gaston, count of Foix, with whom he had also been given authority to treat. He returned home that winter, although he soon entered another contract, on 2 Apr. 1379, to serve under Neville in Aquitaine with 50 men-at-arms and 100 archers for a period of six months. They failed to embark until 18 Oct., but Roches then stayed in the duchy until 2 May 1380. In the spring of 1381 he was preparing to join the earl of Buckingham in Brittany. He and his large contingent of 200 soldiers awaited passage at Dartmouth from 4 Apr. to 19 June, when he received a letter from the King ordering him post-haste to London to assist in the suppression of the Peasants’ Revolt. Five days later he and his men were sent into Hampshire and Wiltshire to put down risings there, and his force was not disbanded until 17 Oct.
In January 1386 Roches was made captain of the important fortress of Brest. The castle was besieged by the Bretons in the early summer, but John of Gaunt, on his way to Castile, came to the help of the garrison and the attackers were beaten off. In March 1387 Roches was empowered to treat with the duke of Brittany for the redemption of the castle, but nothing could have come of this, for Brest remained in English hands for another nine years. That August Roches was ordered to restore goods taken at sea by him and his men from merchants of the Low Countries, and in October he was given control of a fortification near Brest recently captured from the enemy, but his captaincy was brought to an end by the government of the Lords Appellant in the spring of 1388, the earl of Arundel himself taking his place. The termination of his service left Sir John liable for substantial debts incurred on the garrison’s behalf. In October following a barge containing his goods was arrested at Southampton because foodstuffs supplied to Brest had not been paid for; and he had to enlist the support of the Commons of 1391 for his petition for the fair settlement of his accounts to cover the cost of the extra soldiers taken on during the siege.
Roches’s experience of naval affairs was put to considerable use in the 1390s when he was commissioned to hear appeals from the admiral’s court and to investigate jurisdictional conflicts between it and the civic authorities of London. His last recorded miliary action was as a member of the expedition which Richard II led to Ireland in 1394. That he took no part in the King’s final visit to the province in 1399 may have been due to his own advancing years rather than to any change of political allegiance. Indeed, his personal attachments indicate a continuing support for Richard. In 1389 he had been one of those summoned to the Council to arbitrate in a dispute between William Montagu, earl of Salisbury, and his brother John, Lord Montagu; and now, during Henry IV’s first Parliament in 1399, he provided securities for the earl’s nephew and heir, Earl John, who had been challenged by Lord Morley for complicity in the murder of the duke of Gloucester. Then, too, in the following month (November) there erupted a quarrel between him and John, Lord Lovell, over the manors of Huish and Earlscourt in Wiltshire, his protagonist being required to keep the peace under a pain of £200. There may have been another cause for dispute between the two men, for Lovell had rapidly changed his allegiance from Richard II to Henry of Bolingbroke on his return with Richard from Ireland, and among his mainpernors was Archbishop Arundel, one of the new King’s staunchest supporters. Roches had perhaps expressed criticism of his disloyalty.
Now nearing the end of his life, Roches made provision for his family. In 1397 he had granted £20 annual rent from the manor of Shaw to his son William, and in 1399 he made a settlement of the greater part of his estates on his wife and other son, Robert, entailing Waddon and Shaw on William. However, neither of his sons lived to enjoy their inheritance, for when, on 30 Sept. 1400, Sir John died, his heirs were found to be his two daughters. He died owing the Crown some £87, but the King ‘in consideration of his good service’ exonerated his widow and children from payment. A year later, Roches’s mother-in-law, Maud de la Mare, arranged the marriage of one of his daughters, Joan, to Nicholas Baynton, the other, Elizabeth, being already the wife of (Sir) Walter Beauchamp, the future Speaker. Sir John’s widow inherited the de la Mare estates in 1405 on the death of her mother, but lived on for only five years afterwards.