Sir John Minsterworth (died 1377) was a fourteenth-century English knight from Gloucestershire, England, who fought in the Hundred Years' War but was executed by King Edward III for treason. Nothing is known of his early life or upbringing (even, for example, when he was knighted or by whom) but he first comes to prominence during the 1370 invasion of France. The war, under the command of the King's son, Edward the Black Prince, was going poorly and had only recently restarted after a nine-year truce. Minsterworth was part of a force sent to relieve the English command in France under the nominal leadership of Sir Robert Knolles, whom contemporaries praised for his military prowess. Landing in the north, Knolles and Minsterworth carved their way to the west of France. There, divisions among the leaders—which may have been extant since before their campaign began—erupted into mutiny.

Minsterworth may have despised Knolles on grounds of the latter's reputation and status, and, with others, split away from Knolles's main force. Much of the latter was later destroyed by the French army at the Battle of Pontvallain in December 1370. Minsterworth managed to make his way to Brittany, despite frequent ambushes and French raids, and eventually—albeit seeing most of the remnant of his army massacred on the Breton shore—to England. There he attempted to blame Knolles for the disaster, and although Minsterworth's former commander was found culpable of many of the military mishaps that had occurred, Minsterworth did not escape blame either. Soon after, in 1372, he left England and joined the French army. Five years later he met and conspired with a rebel Welsh lord, Owen of Wales, and, for reasons which are now obscure, supported Owen's proposed invasion of England. However, in 1377, while still abroad, he was captured by the English and sent home. Convicted of conspiring with the enemy, he was executed and his corpse quartered and distributed across the kingdom.

Nothing is known of John Minsterworth's early life, although he was probably born in Minsterworth, Gloucestershire, from which he presumably took his surname.^[1] Andrew Ayton describes him as a "shadowy ... man of obscure origins".^[2] His first appearance in the historical record is in 1367 when he contracted with Humphrey, Earl of Hereford to serve in France; Minsterworth was also responsible for recruiting Hereford's large retinue.^[3] The following year he indentured to join the 1370 English expedition to France as part of the ongoing Hundred Years' War. The Historian James Sherborne has said Minsterworth "was to cause much trouble" on the campaign,^[4] and Jonathan Sumption has described the knight as an "ambitious hothead".^[5] The expeditionary force assembled at Rye and Winchelsea in July 1370.^[6] It was to be the first English army to France intended to be led by a commander below the rank of earl^[6] or other peers.^[7] The command was originally given to Sir Robert Knolles of Cheshire, but delays and increasing criticism of the decision^[8] resulted in joint command of Knolles and three other experienced captains, Sir Alan Buxhull, Sir Thomas Grandison and Sir John Bourchier.^[8] John Minsterworth was under Knolles's captaincy.^[6] Sherborne suggests that there may possibly have been "some doubt about Knolles ... even before the army sailed".^[6] This system of shared leadership appears to have led to jealousies and rivalries arising among them, particularly regarding how ransom and booty would be distributed.^{[9][note 1]} Another contributory factor to the captains' discontent may have been that Knolles's original appointment had an "implied mark of distinction" about it, suggests Mark Ormrod.^[11] Minsterworth was the most outspoken of the three other captains.^[12] He seems to have felt himself to be the social superior of Knolles, who had risen through the ranks: The English chronicler Thomas Walsingham describes Knolles as starting off as a "poor and lowly valet".^[9] Minsterworth is known to have called Knolles an "old brigand",^[8] a "tomb-robber"^[13] and a "freebooter" before the troops. He may have hated Knolles, suggests Sumption, and this hatred may have been virulent.^[14]

Although Minsterworth has been called a "comparatively obscure" figure in the political society of the day,^[15] and of "very modest means" financially,^[5] he nevertheless commanded the largest retinue of the army,^[16] second only to Knolles himself.^[17] His contingent comprised ten knights,^[4] around 200 men-at-arms and 300 archers.^[1][5] For this he received £2000 in advance wages.^[18] Geographically his force was recruited from across the country, including locally to Minsterworth—such as Wales and Gloucester—but further afield; Bedfordshire, London, Kingston upon Thames, Daventry, Lincolnshire and Warwickshire.^{[19][note 2]} In this, he was not unlike the great ducal captains, who also recruited far beyond their feudal heartlands, entering into sub-indentures as he did.^[21] Much of this force was composed of "footloose professionals",^[22] as they have been called, often little more than a collection of "outcasts, apostate clergymen and criminals on the run ... who served for loot and pardons".^[5] Minsterworth had to rely on such men because he lacked the recruiting networks in England that a great lord would have possessed through land holding, tenantry and wide-ranging social influence.^[22] While he did recruit men of status who could themselves recruit, such as Sir Thomas Fauconberg^{[note 3]} from the Marches, in many cases his recruitment may reflect connections he had made as a freebooter.^[24] This was in contrast, for example, to Knolles, whose great wealth enabled him to bear the cost of maintaining an army in the field for an extended period.^[25]

Landing at Calais, the army began a chevauchée across northern and southwestern France to Bordeaux. This was intended to draw the French away from Aquitaine, where the Black Prince was about to begin another campaign with John, Earl of Pembroke.^[26] By November 1370, Minsterworth had rebelled under Knolles's leadership,^[1] and became the leader of the increasingly numerous malcontents.^[14] Although by this time Knolles was a soldier of "great fame",^[27] says Rosemary Horrox, Minsterworth neither appreciated nor respected the man or his abilities.^[27] Michael Prestwich has suggested that his eventual desertion from Knolles's army was encouraged by the dire straits Knolles's army now found itself in.^[16] The chevauchée had achieved superficial successes, but, due to its failure to force the French to battle, it was under constant attrition; by now, the army was on the verge of disintegration,^[8] mainly due to Minsterworth's mutiny.^[28] Knolles may have aggravated his fellow captains further by keeping for himself a disproportionally large amount of the ransoms and booty.^[29] This was important to Minsterworth, not only because it impacted his own potential profit, but made it harder to pay his own men, who might, in turn, have deserted him.^[30] The tactical and military failures of the campaign were placed firmly at Knolles's door, and he was increasingly accused of misjudgement and inexperience;^[14] he may have been as unwilling to face the French in open battle as they were him, which could also have increased dissent among men who felt themselves to be "better formed in chivalry";^[31] Minsterworth told his companions, "it redounded to their great dishonour to be subjected" to Knolles.^[32]

A contemporary chronicler relates how "out of envy and self-importance"^[33] the English captains ended up dividing their army into four, and went separate ways,^[33] probably to make enable foraging and increase profits.^[17] Minsterworth's force^[33] was the first to leave; Knolles followed, taking the majority of the army with him.^[29][34] Soon after, in early December 1370, what remained of the English army was routed^[33] at the Battle of Pontvallain.^[35] Minsterworth was not present at the battle,^[36] but he was clearly far enough away to escape the enemy.^[37] It is possible that, by then, he was in communication with the French, and that his information was responsible for the English collapse.^[38] Whatever role Minsterworth had played, on hearing of the result, he immediately escaped into Brittany, probably to Knolles's castle at Derval. There, with Knolles, they spent the winter comfortably. Minsterworth decided to return his army to England early the following year.^{[note 4]} Leaving Knolles in Derval,^[39] Minsterworth led a force of somewhere between a few hundred and 1,100 men^{[note 5]}—possibly including recently arrived, albeit now useless, reinforcements from England^[39]—to the port of Pointe Saint-Mathieu, Finistère. Continual ambushes depleted their numbers en route. Worse news awaited them. When they arrived, there were only two small ships available, far too few for the couple of hundred men who needed transport. Minsterworth was one of the few who could buy a passage; the French soon caught up with those who remained and massacred them.^[36]

On Minsterworth's return to England^[33]—"as one of the only prominent survivors either not dead, still serving in France, or languishing in a French prison"^[40]—a lengthy period of acrimony and recrimination began. While he bore much culpability for the disaster^[41]—being "as guilty as any man for the break up of the army", argues Baker^[39]—at first Minsterworth managed to avoid almost all the blame by putting the responsibility on Knolles.^[41] In July 1372, the King's Council effectively agreed with him and condemned Knolles and Buxhill for the defeat.^[41] The Black Prince and John of Gaunt spoke out for Knolles, though, and eventually the King declared that "he should not be held as responsible as his men for their unruliness, disobedience and arrogance".^[39] Edward ensured that Minsterworth was no longer exculpated:^[42] he was immediately arrested and charged with traducing Knolles.^[42] Minsterworth failed to appear before the council's enquiry, and at this point—"humiliated by the King and frustrated in his ambitions"^[42]—renounced his allegiance to Edward III.^[38] Failure to appear before the council resulted in automatic outlawry, meaning his estates could be seized by the crown.^[43]

Minsterworth left England for France again in 1372,^[42] and it is possible that he was communicating treasonably with King Charles V by this point.^[8] Precisely whether he gave himself up to the French or was captured by them the following year is unknown,^[15] but he was serving in their army by then.^[15][42] The Anonimalle Chronicler condemned this as a betrayal of trust, castigating Minsterworth as having "sold himself to the French",^[44] contra fidem et ligeanciam, or "contrary to his faith and allegiance".^[45] Soon after, on 20 December 1373, the escheator of the Duchy of Lancaster was ordered to confiscate all the lands Minsterworth held of John of Gaunt, Duke of Lancaster, Minsterworth's feudal lord in Gloucestershire and the Welsh Marches.^[43] "More intriguing still", comments Gary Baker, is the fact that he appears to have been accompanied by his old comrade-in-arms, Thomas Fauconberg, who defected at the same time; "the fact that both these men took this huge step must be more than coincidence".^{[46][note 6]}

By 1376, King Charles had formulated a plan to invade England^[48] with a large Franco-Castilian Navy,^[49] or "army of the sea", as the French named it.^[48] Although the intended logistics of this campaign, or how it was to be implemented, is uncertain, Sumption has speculated that a French fleet was to "burn their way west"^[50] along the south coast of England on their way to land Owen of Wales at Milford Haven.^[50] Owen was a pretender to the throne of the Aberffraw princes,^[51] and Charles's plan was for him to lead a French expeditionary force army with the now-renegade Minsterworth. Sumption also, however, points out that it is hard to see what benefit Minsterworth would be likely to get from this escapade or, indeed, what particular advantages the French expected him to bring to it.^[50]

Early in 1377 Minsterworth travelled from France to Castile to arrange the despatch of troops, materiel and transports for the proposed invasion force.^[50] However, he was captured in Pamplona,^[45] Navarre in March by a Gascon squire;^{[52][note 7]} letters discussing the invasion were found on him.^[52] Minsterworth was taken to Bordeaux and then to England.^[52] He was originally landed at Bristol, but as a local landowner, appears to have had some support in the area. The royal council discovered that an attempt at his rescue was planned, and Minsterworth was immediately transferred to the Tower of London.^[45] Under interrogation—including torture—Minsterworth revealed French plans to launch their galley fleet in May the following year.^[15] As a result of his confessions he was tried for treason within the Guildhall, in the City of London, before the Mayor, Nicholas Brembre, and other royal justices.^[45] Here he also confessed to meeting Owen and stated that they were both to have led the invasion.^[15] This was deemed further treason, being "willful support of the King's enemies"^[53] and he was sentenced to be drawn, hanged and quartered.^{[52][note 8]} On 12 April 1377 Minsterworth was executed at Tyburn.^[55]

Before his execution, Minsterworth received permission to write to the King. Although the letter no longer exists, his letter "probably contained an appeal for mercy and the usual kind of promise of information".^[44] He never received a response. Indeed, it was probably opened by the Earl Marshal, Henry Percy, and never seen by Edward.^[44] This may have been, suggests David Moore, because Minsterworth named prominent sympathisers of Owen's in England which it was felt the King should be shielded from.^[56] Following his execution, Minsterworth's body was quartered. One portion was sent to Carmarthen; this being the administrative centre of South Wales, it was probably intended to convey a "brutal message" to any would-be supporter of Owen. Another portion of the corpse was sent to Bristol—where Minsterworth's estates were centred—and the remainder as far apart as Dover and Newcastle.^[15] Owen himself was to be assassinated by an English agent the following year.^[57] Minsterworth's head was placed above London Bridge, where it remained until the Peasant's revolt in 1381, when it was replaced on its pole by the head of Simon Sudbury, Archbishop of Canterbury.^[58]

Minsterworth's later treason, execution, and the subsequent Inquisition post mortem have cast light upon his land-holding, much of which was held directly off John of Gaunt, son of King Edward III. This was particularly concentrated in the southwest of England. His estate included 30 acres (12 ha) of land, five of meadow, and a messuage in Minsterworth itself. He held a corrody in Leonard Stanley, Gloucestershire for fee, as well as another messuage in the City of Gloucester.^[59] Minsterworth also held estates further afield; for example, in South Wales (around Usk),^[1] and Norfolk (in North Barsham).^[60] Since Minsterworth died an outlaw and a traitor, all his lands in Gloucestershire were forfeited to Gaunt per jure ducatus,^[61] while those in Wales and Leonard Stanley went to the King under his right of jure coronae.^{[62][note 9]}

Contemporaries took a dim view of Minsterworth's behaviour. Walsingham described Minsterworth as maim quidem promptus, sed mente fallax et perversus, or "with a willing hand but a deceptive and distorted mind".^[63] In the mid-fifteenth century, the antiquarian John Leland calumniated him as Johannes Menstreworthe Anglus Proditor, or "John Minsterworth English Traitor",^[64] while Holinshed, a century later, said Minsterworth was "a good man of his hands (as we call him) but perverse of mind, and verie deceitful".^[65] Sumption views the later events of Minsterworth's career as perhaps indicating that the knight was afflicted, to some degree, by mental instability.^[5] On the other hand, Sumption also suggests that—in view of how Minsterworth was trusted by Charles to make the arrangements with Castille and to ultimately lead the invasion fleet—"he must have been a plausible talker in spite of his shady past".^[50]

A supposed likeness of Minsterworth—and the story of his execution—is recorded on a version of Ranulf Higden's Polychronicon^{[note 10]} of c. 1377, added by a 16th-century hand. The image is on an otherwise unillustrated mappa mundi at the beginning of the Polychronicon, possibly suggesting that particular version of the manuscript had local provenance.^[67][68]