Alabaster panel showing Thomas Becket praying on his knees, as a sword, carried by a man behind him, comes down on his head.

Who killed Thomas Becket?

By Lloyd de Beer, The Ferguson Curator of Medieval Europe

By Naomi Speakman, Curator of Late Medieval Europe

Publication date: 22 April 2021

The shocking murder on 29 December 1170 of Thomas Becket, Archbishop of Canterbury and thorn in the side of King Henry II, sits at the heart of the Museum's exciting new exhibition Thomas Becket: murder and the making of a saint.

Curators Lloyd de Beer and Naomi Speakman investigate what we know about the perpetrators of this notorious crime. 

Who killed Thomas Becket?

The image of Becket's bloody demise at the hands of four knights from the king's entourage has been depicted countless times in sculpture, wall painting, stained glass, manuscript illumination and metalwork. In the exhibition you see the shocking scene on flasks sold to pilgrims, on brightly enamelled caskets made to hold Becket's relics, and even on a stone font made for a parish church as far away as Sweden.

The archbishop's murder by Reginald Fitzurse, Hugh de Morville, Richard Brito and William de Tracy caused outrage across Europe and continues to fascinate people today. What is astonishing, for an event which took place 850 years ago, is our ability to recount in detail what happened on the day of the crime. In this blog, we track down Becket's murderers and explore who they were and the mysterious circumstances of their deaths. 

Enamelled copper-gilt reliquary showing scenes of the burial and murder of Thomas Becket
Enamelled reliquary casket showing the murder (below) and burial (above) of Thomas Becket, Limoges, France, about 1210.

How do we know what we know?

Within 20 years of Becket's death, at least 13 biographies had been written about him. These 'Lives of St Thomas' were all composed by men who either knew Becket personally or had close associations with the Church. Five were written by eye-witnesses to the murder, including one by a man named Edward Grim, the only person who came to Becket's defence when the knights attacked. For his valiant effort to protect the archbishop, he received a sword in the arm during the fracas.

Given their backgrounds and ties to the Church, it is unsurprising that the biographers, on the whole, paint the archbishop in a positive light, while Henry and his knights are the villains of the story. As a younger man, Becket had lived a secular lifestyle enjoying the pursuit of hunting, playing chess, and even on occasion fighting in battles. But despite this, he is routinely presented in the biographies as a model of virtue who was always destined for future saintly glory. In contrast, the four knights are lambasted as 'men of Belial [the devil]' and 'ruffians', 'madmen' and 'butchers'.

The earliest description of the crime was written by John of Salisbury, an eyewitness and one of the archbishop's closest advisors. In early 1171, John wrote a letter to his friend, the Bishop of Poitiers, in which he recounted the gory details of the murder and the astonishing miracles taking place at Becket's tomb. Copies of the letter circulated widely, and John later expanded it into a full biography which was presented to the Pope as part of a campaign to have the archbishop canonised. This took place in February 1173 when Pope Alexander III officially made Becket a saint, one of the fastest canonisations at the time. A copy of John's eyewitness account can be found in a collection of correspondence related to Becket and Henry's dispute compiled in the wake of the crime, on loan from the British Library. One of the earliest known images of Becket's murder immediately precedes John's description in this manuscript. It is a lively and dramatic scene, remarkable for the illuminator's attention to detail.


Page of book with text and large image depicting scenes, including knights' arrival and Becket's murder
Illumination with scenes from Becket's martyrdom, mid 1180s. © British Library Board – Cotton MS Claudius B II, f.341r.


In the upper part, Becket is interrupted at dinner by the knights' arrival at his palace in Canterbury. They wait outside the door while a servant announces them. Below, to the left, having pursued the archbishop into the cathedral, the knights strike him down. Kneeling before his attackers, Becket is hit on the top of his head by the knight carrying a red shield while Edward Grim, who stands behind holding a cross-shaped staff, receives a blow to his arm. Between Becket and the knights, a piece of the archbishop's bloody severed skull and a fragment from the tip of the murder weapon fall to the ground. This detail of the broken sword can be found in a number of the eyewitness accounts, as Grim states, 'With this blow, the sword itself was dashed on the pavement.' Medieval pilgrims to Canterbury were offered the relic of the swordpoint to kiss, in a chapel located on the site of the murder called the Martyrdom.

Who were the murderers?

As news of Becket's murder spread throughout Europe so too did the notoriety of the four knights. The names Fitzurse, Morville, Brito and Tracy became infamous and they were almost as frequently depicted as Becket himself. All of the knights came from high-standing and land-owning families with close ties to the Crown. Their decision to arrest Becket was no doubt part of a plan to curry favour with the king. When they made their way to Canterbury they did little to conceal their identities or hide in darkness. The archbishop even knew some of the knights personally, greeting Morville by name.

In representations of the event, the numbers of knights present and the way they were depicted varied considerably, but occasionally one of them was marked out. In the illumination above, the red shield of the second knight is decorated with the head of an animal, a visual clue to the man's identity. The bear's head is an allusion to the surname of Reginald Fitzurse, which translates as 'son of the bear'. According to some of Becket's biographers, Fitzurse was the unofficial leader of the group and the bear's head was frequently used to single him out. Fitzurse's prominent role was widely known and medieval pilgrims to Canterbury could even buy and take home a badge in the form of his murder weapon.  A surviving scabbard for a souvenir like this includes a small shield embossed with four tiny bears' heads.

Pilgrim badge representing a decorated sword sheath superimposed with a coat of arms
Lead alloy pilgrim badge of the scabbard of Reginald Fitzurse's sword, England, 1300–1400.

Another pilgrim souvenir names Fitzurse and describes his involvement in the crime. It is a tin-alloy flask made to hold a liquid called St Thomas's Water, a mixture of Becket's blood and water, which was dispensed by the Canterbury monks. Front and back are decorated with two scenes, one of Becket enthroned and another of the murder. Around the frame is a Latin inscription that translates as 'Reginald Fitzurse brought to pass the martyrdom of Thomas.'

Lead alloy pilgrim ampulla with a circular frame with openwork decoration of symmetrical sexfoil and fleur-de-lis motifs and a representation of the front and back view of a seated Becket, depicted in episcopal garb
Lead alloy pilgrim flask with an openwork frame showing figures of Becket and his murder, England, 1200–1300.

A myth debunked

What spurred the knights to action? For many, Becket's death will forever be linked to the famous phrase supposedly uttered in a rage by Henry II, 'Who will rid me of this troublesome priest?'. The knights, within earshot of the king, interpreted Henry to be fed up with the archbishop and conspired to deal with Becket once and for all. Taking it upon themselves they hatched a plan, made their way to Canterbury, and the rest is history.

But, while these events are broadly true, the exact words Henry said will never be known for certain. His famous phrase can only be traced back as far as the 1700s. Becket's early biographers attributed a few different phrases to the king and although their accounts differ, the meaning remains clear. Henry, overwhelmed by his anger with Becket, wanted the entire court to hear of his displeasure. Whether or not he wanted anyone to murder the archbishop is impossible to say!

Garnier of Pont-Sainte-Maxence, a French biographer of Becket who travelled to Canterbury to investigate the facts and even interviewed the archbishop's sister, wrote that Henry said:

A man… who has eaten my bread, who came to my court poor, and I have raised him high – now he draws up his heel to kick me in the teeth! He has shamed my kin, shamed my realm; the grief goes to my heart, and no one has avenged me!

Trans Michael Staunton, The Lives of Thomas Becket, Manchester: Manchester University Press, 2001, p. 189.

Although Henry later distanced himself from the knights' actions, many blamed him for Becket's death. One of the objects on loan to the exhibition is a font from the parish church of Lyngsjö in southern Sweden. It shows how, in the aftermath of the crime, Henry was seen as its instigator. Made around 1191, the upper half of the bowl shows a scene of Becket's murder. To the left, the king sits enthroned, named by a scroll reading 'REX:HRICVS' (King Henry). He points to a knight, ordering him to join in with the others who have already begun attacking the archbishop.

Crime and punishment

Henry's appearance on the Lyngsjö font raises the question of what punishment he and the murderers faced for Becket's death. Following the crime, the knights trashed and looted the archbishop's palace, probably in search of incriminating evidence which they could use against him. They then made their way to Saltwood Castle, located 15 miles south of Canterbury. From there, they travelled to Knaresborough Castle in Yorkshire, where they stayed for about a year. Surprisingly, the knights faced little initial backlash from the king and appear to have been left in peace during their time in Knaresborough. Behind the scenes however, Henry barred their male heirs from inheriting property – a serious blow.

To absolve themselves, the knights made their way to the Pope in Rome, who commanded them to go on pilgrimage to the Holy Land. All four are believed to have died either in Jerusalem or on their way there. William de Tracy left us with a final clue to his whereabouts, a surviving charter dating from 1173 to 1174, now in the library and archive of Canterbury Cathedral, issued by him in the Italian city of Cosenza. Desiring forgiveness for his involvement in the murder, he grants gifts to the monks of Canterbury and asks that they pray for his soul.

As for the king, his punishment was light. Two years after Becket's death, he performed a public penance in the Norman towns of Avranches and Caen. Afterwards, the Pope absolved Henry of any wrongdoing. But the king's public demonstrations did not end there. In July 1174 he was facing the greatest challenge to his authority yet, a civil war brought about by his sons and their mother, his wife, Eleanor of Aquitaine. In the midst of this war, he finally visited Canterbury and the resting place of his old adversary. In an astonishing public humiliation, the king walked barefoot through the city and knelt before Becket's tomb in the Cathedral crypt. He acknowledged his involvement in the crime and was punished by monks. The next day, Henry's fortunes changed. His men won a decisive battle and his success was widely attributed to the intervention of Saint Thomas of Canterbury.

From then on, Henry adopted Becket as his protector. He made numerous gifts to the cathedral and visited it regularly on pilgrimage. In a royal charter, on loan to the exhibition from Canterbury Cathedral, Henry promises to protect the rights of the Canterbury monks in perpetuity. It came endorsed by his great seal, a magnificent wax image of the king enthroned with sword in one hand and orb in the other.

Parchment bearing writing with wax seal attached at bottom
Writ of Henry II with his Great Seal, c. 1175. Parchment with wax seal. CCA-DCc-ChAnt/C/19. © The Chapter, Canterbury Cathedral.


Despite Henry's penance and personal endorsement of Becket's burgeoning cult, he could never escape his association with the murder. A later genealogy of English kings, on loan from the British Library, shows both men locked in a heated argument. Enthroned on the left, Henry presses a finger emphatically into his open palm while the Archbishop raises a hand in disagreement.

Image of Henry II and Becket facing each other both with hands raised, in garments reflecting their standing
Henry II and Becket arguing in a genealogy of the Kings of England, about 1307–1327. © British Library Board – Royal MS 20 A II, f. 7v.

Their dispute became the defining feature of the king's reign, whereas Becket would be raised up as a champion among those who sought a model of opposition to royal tyranny and a defender of the rights of the Church.

Thomas Becket: murder and the making of a saint ran from 20 May to 22 August 2021. To find out more about the exhibition, visit  

To find out more about Becket's life and legacy, read Thomas Becket: the murder that shook the Middle Ages

Supported by:

The Hintze Family Charitable Foundation

The Ruddock Foundation for the Arts

Jack Ryan and Zemen Paulos