In 1367, when his maternal uncle, Sir William Felton, was slain in Spain, Thomas Swinburne, then aged ten, became coheir with his cousin William, son of Robert, Lord Hilton, to certain of the Felton estates. Together he and William disputed the claims of Sir John Felton, their uncle of the half-blood, but sir John as the heir male managed to secure the more important properties. Nevertheless, in 1368 Thomas’s father obtained custody of some lands at Stamfordham, Heugh, Ouston and South Milbourne (Northumberland), which formed part of the inheritance, while Lord Hilton procured from the bishop of Durham keeping of various holdings in Medomsley and Hamsterley, Durham. Thomas and his cousin both came of age before February 1379,
Swinburne was to become one of the foremost military captains of his day. His training took place in military captains of his day. His training took place in the north on the Scottish borders and, having been knighted by 1380, he rose rapidly to be appointed joint keeper with Sir Richard Tempest of the strategically important castle of Roxburgh less than five years later. Both he and his father were connected with Sir Thomas Percy, and it was under the command of Percy’s brother Henry, earl of Northumberland, that he and Tempest served in 1385, providing substantial reinforcements for Richard II’s army intending to invade Scotland. Swinburne evidently made a favourable impression on that campaign, for from February 1386 onwards he was put in sole command at Roxburgh, and his contract was renewed for a further three years in May 1387. That November he made arrangements to ship from Essex and London cloth for the livery of his soldiers and equipment for the use of the garrison, but he was not to retain his post for long. In March 1388 the earl of Northumberland complained that, although he had paid the Scots compensation for breaches of the truce, he had been unable to obtain reimbursement from certain of the culprits, who included Swinburne; and that same month the latter was bound in obligations of 200 marks while the Council (now controlled by the Lords Appellant) considered whether he should be held responsible for payment of a fine of half that sum imposed on one of his men for slaying a Scot. In July, despite his indenture to serve at Roxburgh until 1390, he was removed from the keepership. For a while Swinburne was generally under a cloud: two years later he was required under pain of forfeiting 500 marks to answer Edward, duke of York, for any injuries he had done to the duke’s tenants during his term as York’s bailiff of the lorship of Tynedale.
Whether as a reaction to his dismissal or as a development of earlier inclinations, Swinburne now expressed overt sympathy for the victims of the Appellants. In November 1388 he had stood surety at the Exchequer for Sir Michael and Sir Edmund de la Pole, respectively son and brother of the King’s favourite, the exiled earl of Suffolk, and in the following February he offered similar support to Sir Roger Fulthorpe’s son.
After Richard II had regained control of the government, Swinburne was appointed warden of Guînes castle, thus being removed to a very different sphere of military activity. As an outcome, he gradually cut off his ties with the north of England and took up more permanent residence in Essex, where for the previous few years he had been landlord of a manor in East Mersea, settled on him by his father, Sir Robert. The latter died in 1391, whereupon Sir Thomas attempted to wrest seisin of other Swinburne estates from his stepmother, Joan, and from his father’s feoffees. Hauled before the courts, he was required to furnish securities of £1,000 that he would not harm the widow, her children, servants and tenants; while bonds in even greater sums sealed at that time were probably intended to ensure that he would keep the peace. The family lands at Gunnerton and elsewhere in Northumberland, which he had secured without difficulty, he now put into the hands of trustees to supervise during his absence abroad.
In the summer of 1392 Swinburne, having decided to go on a pilgrimage, appointed his friend and distant kinsman, Sir William Swinburne of Capheaton, as his attorney to receive all debts owing to him in the north of England, and at the same time he sold to Sir William all the northern lands of his Felton inheritance. He left his post as Guines on 6 Aug. and travelling via Venice, Alexandria, Cairo, Mount Sinai and Bethlehem, reached Jerusalem in time for Christmas. After visiting Damascus he crossed Lebanon to Beirut, sailing from there to Rhodes and thence home to England. It is clear from the fact that he did not leave Beirut until 15 Jan. 1393 that he must have been elected to the Parliament due to assemble five days later in his absence. Furthermore, it seems most unlikely that he reached Westminster before the dissolution on 10 Feb. Nevertheless, writs were issued for the payments of his expenses in attending the Commons. In October Swinburne was summoned before the Council ‘concerning certain matters to be objected against him’, and he was removed from command at Guines within a month. Whatever his misdemeanours they cannot have been too serious, or else were quickly forgotten, for he was given the prestigious post of captain of Calais a year later. When he surrendered that captaincy in October 1395 it was in return for a grant of the reversion, after the death of Richard Holme, of the lordship of Hammes and custody of the castle there, and until this fell to him he was to enjoy a handsome annuity of 100 marks at the Exchequer as retained by the King. In the event he and Holme agreed that the latter would relinquish his patent in exchange for Swinburne’s annuity, and in March 1397 Sir Thomas was granted Hammes for life. He spent most of 1397 at home in Essex, putting his own affairs in order and coming to amicable terms with his father’s feoffees, and from July to November he served on the local bench. A deputy officiated in his place at Hammes, although in May 1398 he himself was actively involved in the victualling of the stronghold, and he may have spent most of that year in the march of Calais. Swinburne evidently remained close to Richard II: on 20 Feb. 1399 when he was given leave to go to ‘divers parts of the world, for urgent causes’, he was described as a knight of the King’s chamber.
Swinburne may well have been overseas when Richard was deposed, but he showed no reluctance to accept the new regime, and on 30 Oct. 1399 Henry IV, who was fully aware of the need to conciliate men of military calibre, confirmed him in his post at Hammes. Subsequently, Sir Thomas became a ‘King’s knight’ and obtained appointment as constable of Clare for the duration of the earl of March’s minority. The premature loss of this particular post, in July 1403, may be attributed to his connexions with the earl of Northumberland, whom he had recently been serving as lieutenant in his capacity as constable of England. Even so, there is no evidence to implicate him in the Percy rebellion. Indeed, that autumn he served under the earl of Somerset in the campaign directed against the Welsh rebels, and it was at this time, too, that Henry IV began to employ him for diplomatic missions using Calais as a base. Although he was appointed to treat for truces with the French and Flemings in the autumn and winter of 1403, negotiations were not effectively opened until the following summer, when Swinburne was involved in correspondence with the Four Members of Flanders regarding the restitution of goods stolen from English merchants, piracy, various acts of hostility and reprisal, and the capture of the bishop of Hereford. In September 1404 communication with the French was broken off when news reached the envoys that a naval force was being assembled to assist the Welsh, and Swinburne went home with little achieved.
In the meantime, during his earlier stay in England, from 1400 to 1403, Swinburne had performed various services for his associates. For instance, he had stood surety for William, Lord Clinton (who had married his stepdaughter, Anne Trivet), acted as a feoffee of the estates of Sir Andrew Butler, and taken on the executorship of the will of Robert Bassingbourne of Cambridgeshire. Subsequently he assisted his cousin Joyce Vyne (daughter of Sir Thomas Cornard) in various property transactions, and he became a trustee of the manorial holdings of his nephew, William Rookwood, and of the King’s councillor, John Doreward.
Swinburne was succeeded as mayor of Bordeaux before November 1411, although he remained in command at Fronsac until February following. He then returned to England, where he successfully secured the sum of £2,300 to pay his men. While engaged in preparations to sail back to his post, he fell ill in London, made his will on 9 Aug. and died the same day. He was buried next to his father in Little Horkesley priory in an altar tomb with magnificent brasses built on the instructions of his half-brother, William. Sir Thomas left 600 marks to be distributed for the souls of his father and progenitors and the residue of his goods to his executors (his nephew William Rookwood and Thomas Barton alias Hammes) to spend on pious uses. His consort, Elizabeth Trivet, and Sir Thomas Erpingham (former chamberlain to the King) were named as overseers of the will. Although Barton promptly sailed for France with money for the garrison of Fronsac, Swinburne’s affairs abroad were not to be finally wound up for at least 15 years.