The Luttrell Psalter, now held in the British Library, is a gorgeous, lavishly illustrated manuscript dating to sometime between about 1320 and 1330, i.e. it was made either late in Edward II's reign or early in Edward III's, for Sir Geoffrey Luttrell. As well as commissioning one of the most stunning pieces of art to survive from medieval England, Geoffrey took part in a raid on Sempringham Priory in Lincolnshire in 1312. Here's a post about it, with some information about Geoffrey and his family.
Sir Geoffrey Luttrell was born on 23 or 24 May 1276 early in Edward I's reign and died on 23 May 1345, his sixty-ninth birthday or the day before. He was granted the lands of his late father Robert Luttrell, who died shortly before 18 June 1297, on 3 November 1297 after he proved he was twenty-one.  The name was also spelt Loterel, Loterell, Louterel, Louterell, Lutterel or Lutterell, and the family held the manors of Irnham in Lincolnshire, Hooton Pagnell in Yorkshire, Saltby in Leicestershire, and Gamston and Bridgford in Nottinghamshire. Irnham was their chief manor. Geoffrey married Agnes Sutton, who died in 1340, and their son and heir was Andrew, Lord Luttrell, who was born around Easter (15 April) in 1313: he was 'aged 32 years and more at the feast of Easter last' in June 1345. Somewhat peculiarly, Pope John XXII granted Geoffrey Luttrell and Agnes Sutton a 'dispensation...to remain in the marriage which they contracted in ignorance that they were related in the third and fourth degrees' as late as October 1331, decades after they wed.  Like his father, Andrew Luttrell lived a long life and died on 6 September 1390 at the age of seventy-seven, having married firstly Beatrice Scrope, who appears in the Luttrell Psalter and was one of the daughters of Sir Geoffrey Scrope (c. 1285-1340), chief justice of the King's Bench, and secondly Hawise Despenser (b. 1344/45, d. 10 April 1414), mother of his son and heir Andrew the younger, born c. 1364. Hawise was a great-granddaughter of Hugh Despenser the Elder (1261-1326), earl of Winchester, via his younger son Philip Despenser (d. 1313). The Luttrell/Despenser wedding took place in 1363 in the castle of Bourne in Lincolnshire, held by the Despensers' cousin Blanche of Lancaster (d. 1380), dowager Lady Wake.  Andrew Luttrell was fifty when he married his second wife and not even seven when he married his first: he and Beatrice Scrope were wed by 22 February 1320, when they appear on record as 'Andrew son of the said Geoffrey [Luttrell] and Beatrice his wife'.  Beatrice Scrope Luttrell died childless sometime after 3 April 1345, when she was left ten marks (£6.66) in her father-in-law Geoffrey's will. It's a pity the will doesn't mention the gorgeous Psalter Geoffrey commissioned. EDITED TO ADD: 'Beatrice Luterelle' appears on the Close Roll on 18 October 1350, granted permission to travel to Rome on pilgrimage with four attendants. 
Below, the brass of Andrew, Lord Luttrell (1313-90) in St Andrew's Church, Irnham, Lincolnshire.
Below, Sir Geoffrey Luttrell on horseback in one of the Luttrell Psalter's gorgeous illustrations, with his wife Agnes Sutton and their daughter-in-law Beatrice Scrope, Andrew's first wife.
The Luttrells' Lincolnshire manor of Irnham lies about ten miles from Sempringham Priory, which was founded by St Gilbert of Sempringham (d. 1189) and was the first house of his Gilbertine Order. One of Sempringham's residents in 1312 was Gwenllian ferch Llywelyn (d. 1337), then aged thirty, daughter of Llywelyn ap Gruffudd, prince of Wales and Eleanor de Montfort, and a second cousin of Edward II (they were both great-grandchildren of King John). Edward granted Gwenllian, whose name usually appears in English records as 'Wenthlian(e)', an allowance of twenty pounds a year for life.  Another nun of Sempringham was Geoffrey Luttrell's daughter Isabella, Andrew's sister, and in 1322 Edward II sent his niece Margaret de Clare to live there for a while, with a number of attendants, after her second husband Sir Hugh Audley took part in the Contrariant rebellion.
Below, the church of Sempringham Priory; pics taken by me during a visit in 2019. The priory was closed down in 1538 during the Dissolution.
The memorial to Gwenllian at Sempringham, in Welsh and English.
The first evidence that a raid had taken place on Sempringham Priory appears in an entry on the Patent Roll dated 27 July 1312, a time when Edward II was dealing with the aftermath of Piers Gaveston's death on 19 June, and while Queen Isabella was pregnant with Edward III. The king gave a commission of oyer et terminer to three men 'on the information of H. de Bello Monte', i.e. Sir Henry de Beaumont, a French-born kinsman of Edward II who was an important landowner in Lincolnshire; he owned Folkingham Castle and the manor of Heckington, among others. According to the commission, the prior of Sempringham had complained that 'Geoffrey Luterel of Irnham', Edmund Coleville, John son of John Gobaud, Roger Birthorpe and his brothers John and Thomas, John Graveneye, Willaim Pleseleie and John Hunte, and unnamed others, 'broke his doors and walls at Semplyngham, co. Lincoln, and carried away his goods, and assaulted Thomas Hougate and John Irnham, his fellow canons, and also certain of his men and servants'. Another entry on the Patent Roll dated 7 September 1312 relates to a retaliatory attack: John, prior of Sempringham, Thomas Hougate and John Irnham, and ten named other men, attacked Roger Birthorpe's home at Birthorpe. They broke into his park and stole some of his animals, 'carried away his goods' and assaulted three of his servants. 
The village of Birthorpe is just two miles from Sempringham Priory and also two miles from Folkingham, chief manor of Edward II's kinsman Sir Henry de Beaumont who reported the attack on the priory, and the other men named as taking part in the raid on Sempringham were also local. Sir Edmund Coleville (25 January 1288 - shortly before 16 March 1316) was the lord of Castle Bytham sixteen miles from Sempringham Priory. I'm unfamiliar with the Gobaud family, though Guy Gubaud, who was most probably the older brother of 'John son of John Gobaud', died not long before 8 May 1314 and left property in Lincolnshire to his thirteen-year-old son. Guy's father John died in 1310. 
As well as the information on the Patent Roll, a petition still exists in the National Archives which appears to date to shortly after Edward II's downfall in 1327.  It was presented by Roger Birthorpe. The prior of Sempringham in 1312, called simply 'John' on the Patent Roll, is now named as John Camelton, and Roger Birthorpe claimed that he had lawfully taken some of the prior's cattle to settle a dispute between them. Roger went on to say that he had gathered 'other great lords and good men' of the locality, including Geoffrey Luttrell, Edmund Coleville, and Guy Gubaud, apparently an error for Guy's younger brother John. The lords, supposedly, went to Sempringham to have a reasonable conversation with the prior, but he maliciously broke down his own doors to make it look like the lords had done it, and raised the hue and cry against them.
Below, part of Roger Birthorpe's petition of 1327, with Geoffrey Luttrell's name.
Roger Birthorpe also stated that the prior of Sempringham had the support of 'Sir Hugh Despenser and his sisters, ladies in the said priory' (Mons' Hughe le Despenser et ses seors dames en la dite priorie) in this matter. He didn't specify whether he meant Hugh the Elder (born in 1261 and in his early fifties in 1312) or his son Hugh the Younger, who was twenty-four or so, though at this stage in Edward II's reign, the name Hugh Despenser used on its own inevitably meant Hugh the Elder. Hugh the Younger had four sisters, but the eldest two, Alina and Isabella, were married in 1312 and were definitely not nuns of Sempringham, and the youngest two, Margaret and Elizabeth, seem too young to be involved, as they were almost certainly born in the second half of the 1290s or at the beginning of the 1300s. Hugh the Elder also had several sisters or half-sisters, daughters of his father Hugh Despenser, justiciar of England, killed at the battle of Evesham in 1265 fighting with Simon de Montfort, earl of Leicester. One (half?-)sister, Eleanor (d. 1328), was the mother of Sir Hugh de Courtenay of Okehampton (1276-1340) and grandmother of Hugh de Courtenay, earl of Devon (1303-77), and another, Joan, married Sir Thomas Furnival (d. 1332). It's certainly possible that Hugh Despenser the justiciar (d. 1265) had other daughters who became nuns at Sempringham. Hugh Despenser the Younger's third daughter Eleanor did end up as a nun of Sempringham, but that was much later, and 1312 was a few years before she was even born.
Mons' Hughe le Despenser in Roger Birthorpe's petition.
It's impossible to tell whether the alleged involvement of one of the Hugh Despensers and his sisters in the whole affair is true, or whether the name was added to the petition after the Despensers' downfall and executions in 1326 to give it more weight. In 1327, at the start of Edward III's reign and during the regency of his mother Isabella, numerous petitions were issued against the two Despensers. Most of them were true; some were probably not. The Despensers were, however, connected to the Luttrell family and to the county of Lincolnshire in some ways. On 5 August 1309, a clerk named John Elleker who had abducted Geoffrey Luttrell's young daughter Elizabeth, Andrew's older sister - Andrew wasn't even born in 1309 - was pardoned at the behest of Hugh Despenser, almost certainly the Elder.  Hugh Despenser the Elder's second son Philip (b. c. 1292/94, d. 1313) married the Lincolnshire heiress Margaret Goushill or Gousell (1294-1349) before 29 June 1308, probably not too long before.  Philip and Margaret's granddaughter Hawise Despenser (1344/45-1414) was the decades-younger second wife of Andrew Luttrell, as noted above, and this cadet branch of the Despenser family were firmly Lincolnshire-based for generations. On 17 May 1313, Edward II granted the fines due from John Graveneye, one of the men who attacked Sempringham Priory who was 'convicted...of diverse trespasses committed by him and others against the prior of Sempyngham' to Sir John Haudlo, a long-term adherent of Hugh Despenser the Elder, 'on the information of H. le Despenser'. 
Roger Birthorpe also stated in his petition that because of the 'great malice' of John Camelton, prior of Sempringham, he had to leave England altogether and move to Ireland, and was declared an outlaw. Furthermore, his manor of Birthorpe, worth £40 a year, was granted to Sir Henry de Beaumont. There is evidence that Birthorpe did indeed pass to Henry (d. 1340) and his son and heir John de Beaumont (d. 1342), though isn't listed in their inquisitions post mortem. 
It's often difficult to get to grips with these local feuds and to figure out what was really going on, or to determine who, if anyone, was more at fault or was the more injured party. Another feud that I've always found amusing took place in Essex a few decades later, between Maud de Vere née Ufford (1345/46-1413), dowager countess of Oxford, and the prior of Earls Colne. Yes, another prior. The prior claimed that the countess had him assaulted and imprisoned, and dragged him around Essex 'shamefully clad'. Maud countered that the prior and his men besieged her in her home in the village of Earls Colne, and 'threatened her with arson and other evils'.  The raid on Sempringham Priory in the summer of 1312, and the prior's revenge attack on one of the perpetrators - the one who lived closest to the priory, coincidentally or not - is all too typical of the era, and the real interest of this one lies in the involvement of the man who commissioned the Luttrell Psalter. And to finish, just one last thing about this attack on Sempringham Priory. It presumably took place not long before 27 July 1312, when it's first mentioned in the chancery rolls. Andrew Luttrell was said in 1345 to have been born around Easter 1313, and as Easter Sunday fell on 15 April in 1313, Geoffrey Luttrell and Agnes Sutton must have conceived him around the time of the raid.
1) CCR 1296-1302, p. 70; CFR 1272-1307, p. 387; CIPM 1291-1300, no. 406; CIPM 1336-46, no. 589.
2) Calendar of Papal Letters 1305-41, p. 368.
3) Early Lincoln Wills, ed. Alfred Gibbon, pp. 18-19, 56-7, 99; CIPM 1384-92, nos. 1008-9; CIPM 1392-99, nos. 1062-63; CIPM 1413-18, nos. 154-56; CIPM 1418-22, nos. 30-32.
4) CPR 1317-21, p. 424.
5) Early Lincoln Wills, pp. 18-19; CCR 1349-54, pp. 271-2; TNA, SC 8/246/12265.
6) Calendar of Memoranda Rolls Michaelmas 1326-Michaelmas 1327, no. 2160.
7) CPR 1307-13, pp. 530, 533, 584, 598.
8) CIPM 1307-17, nos. 157, 473, 592; CFR 1307-19, pp. 72, 74, 199.
9) TNA, SC 8/34/1671, and see Joyce Coleman, 'New Evidence about Sir Geoffrey Luttrell's Raid on Sempringham Priory, 1312', British Library Journal, 25 (1999), pp. 103-28.
10) CPR 1307-13, p. 181.
11) Calendar of Chancery Warrants 1244-1326, p. 275.
12) CPR 1307-13, p. 584.
13) CCR 1343-46, pp. 201, 321; CIM 1308-48, no. 1835; CIPM 1336-46, nos. 271, 381.
14) CPR 1399-1401, pp. 414-15, 519.