How Thomas Becket Was Really Murdered in Canterbury Cathedral

Thomas Becket’s murder inside Canterbury Cathedral in 1170 shocked medieval England and quickly turned him into a saint. But what actually happened in those final moments—and why did his death come to be seen as something more than a brutal killing?

By Lorris Chevalier

On 29 December 1170, Thomas Becket, Archbishop of Canterbury, was brutally slain within his own cathedral. By the following day, miracles were already reported at the site of his body, and Canterbury swiftly became one of the most important pilgrimage destinations of the Middle Ages.

Less than four years later, on 8 July 1174, King Henry II of England, indirectly responsible for Becket’s death, submitted himself to public penance at the martyr’s tomb. Amid rebellions, including those led by his own sons, the king’s dramatic act of repentance was followed, within weeks, by a remarkable restoration of peace.

Taken separately, neither the murder nor the repentance was entirely exceptional in medieval society. Violence between secular and ecclesiastical powers was common, as were sudden and theatrical acts of contrition. Yet the intertwined destinies of Becket and Henry II, once allies, later adversaries, captured the imagination of contemporaries. Their story seemed bound by deeper forces, where violence and sanctity converged.

The Murder: A Scene of Calculated Violence

To tell the story of Thomas Becket’s murder, we turn to La Vie de saint Thomas Becket by Guernes de Pont-Sainte-Maxence, one of the earliest accounts of the events at Canterbury. Written soon after Becket’s death, the 6,000-line poem was based in part on interviews with eyewitnesses, leading historians to regard it as a highly reliable narrative.

The conflict between Becket and Henry II had lasted seven years, centred on the Constitutions of Clarendon, which threatened the independence of the Church. After six years of exile in France, Becket returned to Canterbury—only to face fatal consequences.

Four knights acting in what they believed to be the king’s will, travelled secretly to England and confronted the archbishop.

A first altercation nearly turned deadly:

Se li felun eussent arme u cultel eü,
Entr’eaus l’eüssent mort (…)
Nis pur poi qu’il ne l’orent ocis e abatu
Del bastun de la cruiz. Mais Deus l’ad destolu.
(v. 5247–5250)

If the felons had had weapons or knives,
They would have killed him among themselves (…)
Indeed, they nearly struck him down and slew him
With the staff of the cross. But God prevented it.

Moments later, the knights returned armed, forcing their way into the cloister and seizing Becket:

Dunc l’unt saisi as puinz li fil a l’aversier,
Sil comencent forment a traire e a sachier,
E sur le col Willaume le voldrent enchargier ;
Car la hors le voleient u oscire u lïer.
(v. 5546–5549)

Then the sons of the adversary seized him by the fists,
They began violently to drag and pull him,
And William sought to force him by the neck;
For they wished either to kill him outside or bind him.

Becket resisted, clinging to a pillar, aided by the monk Edward Grim. The first blow fell:

Enz el chief de l’espee grant colp li vait duner,
Si que de la corune le cupel en porta
E la hure abati e granment entama.
(v. 5585–5587)

Into his head he struck a great blow with the sword,
So that he sliced off part of the crown
And shattered the skull, grievously wounding him.

More blows followed until Becket collapsed. Finally:

Sur le col saint Thomas mist sun pié e ficha ;
Le cervel od l’espee hors del chief li geta.
Desur le pavement, e a cels s’escria :
“Alum nus en, fait il, ja mais ne resurdra !”
(v. 5632–5635)

Upon Saint Thomas’s neck he set and pressed his foot;
With the sword he scattered his brains from his head
Across the pavement, and cried out to the others:
“Let us go; he will rise no more!”

The brutality was undeniable, yet Guernes refrains from rhetorical outrage. Instead, the narrative remains stark, almost restrained: suggesting that the meaning of the act lies beyond mere violence.

From Murder to Martyrdom

The killing was immediately interpreted not simply as a crime, but as a martyrdom. Medieval observers understood martyrdom as a form of sacrifice—an offering of a victim to God.

Becket’s death was thus aligned with Christ’s Passion:

E si cum en Calvaire unt Deu crucifié…
(v. 5616)

And just as God was crucified on Calvary…

This identification transformed the event. The site of his death became an altar; his blood, once a sign of defilement, became a source of healing.

Icel sanc de pechié covint par sanc laver.
(v. 5559)

That blood of sin had to be washed by blood.

Miracles soon followed:

Mult granz miracles (que Deus) fait pur lui e nuit e jur (…)
E les morz fait revivre, mutz parler, surz oïr…
(v. 5885–5890)

Great miracles God performs through him day and night (…)
He makes the dead live again, the mute speak, the deaf hear…

Thus, the violent death was reinterpreted as beneficial: a sacrificial act restoring order.

Violence, Sacrifice, and Social Order

The murder of Becket occurred after years of escalating tension. His death acted as a release:

Par Thomas est li regnes trublez e empeiriez ;
S’il esteit mort, ço dit, tut sereit apaisiez.
(v. 5128–5129)

Through Thomas the kingdom is troubled and worsened;
If he were dead, it would all be at peace.

In this sense, Becket became a scapegoat—his death channeling collective conflict into a single act of violence, which paradoxically restored harmony.

The King’s Penance: A Second Sacrifice

When disorder returned in 1173–1174, Henry II interpreted it as divine vengeance. He responded with an extraordinary act of penance at Canterbury.

His actions mirrored a sacrificial ritual: fasting, pilgrimage, and ultimately self-inflicted suffering through public flogging. This was not merely repentance—it was a symbolic substitution, the king offering himself as a victim in place of the community.

Guernes de Pont-Sainte-Maxence interprets the outcome clearly:

Mais Deus ad, bien le sai, cel’ ire desturnee
Qu’il aveit al realme e al pueple aprestee.
(v. 5726–5727)

But God, I know well, has turned away the wrath
He had prepared for the kingdom and the people.

And finally:

Or a Deus parduné al rei sun maltalent.
(v. 6061)

Now God has forgiven the king his wrongdoing.

Peace followed swiftly, reinforcing the belief that ritualised violence could counteract destructive violence.

The murder of Thomas Becket cannot be understood solely as a political crime. It reveals a deeper medieval mentality in which violence and the sacred were inseparable.

The act itself, its transformation into martyrdom, the miracles that followed, and the king’s penitential ritual all belong to a single framework: sacrificial thinking. Within this worldview, violence is both the problem and the solution—capable of destroying order, yet also of restoring it when properly directed.

In this light, Becket’s death was not merely an assassination. It was a sacrificial event that reshaped the political, religious, and social landscape of medieval England.

Dr Lorris Chevalier, who has a Ph.D. in medieval literature, is a historical advisor for movies, including The Last Duel and Napoleon. Click here to view his website.

How Thomas Becket Was Really Murdered in Canterbury Cathedral