Thomas Becket was one of the most powerful figures of his time, serving as Royal Chancellor and later as Archbishop of Canterbury, but his murder at Canterbury Cathedral changed the course of history forever.

Initially a friend of King Henry II, Becket became engaged in a bitter dispute with the King which culminated in his shocking assassination by knights in 1170.

To mark the 850th anniversary of this historic crime, The British Museum is staging a major exhibition about Becket's tumultuous journey from a London merchant's son to Archbishop.

And it will feature as its centrepiece an entire stained-glass window from Canterbury Cathedral.

The exhibition will also tell the story of him being revered saint in death to a 'traitor' in the eyes of Henry VIII, more than 350 years later.

It is a story of betrayal, of the perceived abuse of power and those who fall for standing in the way of the Crown.

It will also explore Becket’s rise and fall, and unpick the events which led to a murder which shook the Middle Ages.

Artefacts from the museum's collection as well as other important items on loan from other major collections from across the UK and around the world will be featured.

Who was Thomas Becket?

Becket was born in Cheapside, London around 1120 and was a second-generation French inmigrant.

His parents, originally from Normandy, were named Gilbert and Matilda, but had left the country following the Norman Conquest.

At the time his family were not powerful or rich but his father was a well-connected merchant.

Becket went to school at Merton Priory in London, which is an English Augustinian priory founded in 1114 by Gilbert the Norman, and he also spent a few years studying in Paris.

He was then employed by one of his dad's friends as a clerk for Theobald, the then Archbishop of Canterbury.

Becket was described by his peers at the time as intelligent, charming and authoritative and, in 1155, he got his big break.

Theobald, who recognised his talents, suggested that Henry II appoint him as Chancellor of England.

This quickly saw Becket and the King becoming friends and the pair would hunt, game and travel around the country together.

Becket was said to embrace life in the royal court and enjoyed lavish parties, vast wealth - decorating his homes with beautiful furniture and ornaments - and made various trips to France on his own ship.

When the job of Archbishop of Canterbury became vacant, Becket was put forward for the role.

The King was keen to appoint his friend as the Archbishop, but Becket was an unlikely candidate. He wanted him to continue his role as Chancellor of England.

But if he put Becket in both positions the King could exercise greater authority over the Church as well as the State.

Becket was appointed Archbishop on May 23, 1162 and was consecrated (officially blessed) on June 3.

Fatefully, later that year and against Henry II's wishes, he resigned as Chancellor.

This decision drove a huge wedge between him and the King which was never repaired and would deteriorate further.

Several disputes between the pair then happened regarding the division of power between the Crown and the Church.

By 1164, tensions were reaching boiling point and in October that year, he was summoned to appear before the King’s council and ordered to forfeit all his property.

He refused to accept the terms of this punishment and, fearing more repercussions, fled to France.

Life in exile

He remained in exile there for six years and during this time Henry II flexed his power in England.

He snubbed his old friend’s authority and in June 1170, had his son, Henry the Young King, crowned.

This was done by Becket’s enemy, the Archbishop of York. Becket then appealed to the Pope for help and and, under pressure, the King agreed to reopen negotiations with his estranged friend.

The pair then spoke privately for the first time since 1164, and Henry II promised to restore Becket as Archbishop of Canterbury.

He was assured at this point it would be safe to return to England, but he wanted to punish those involved in the unauthorised coronation.

Just before he left France to return to England he wrote three letters expelling the Archbishop of York and two bishops from the Church.

This act was to have devastating consequences upon him when he returned to the country.

He returned on December 1, 1170 and, according to reports from the time, was welcomed back to Canterbury Cathedral by rejoicing monks and cheering crowds.

However, he faced increasing hostility by the authorities loyal to Henry II.

The Archbishop of York and the Bishops of London and Salisbury were furious they'd been ex-communicated.

So they travelled to King Henry’s royal court in Normandy where they relayed Becket’s actions.

He was outraged by the news.

One of Becket’s biographers records Henry’s words upon hearing the news as: "What miserable drones and traitors have I nurtured and promoted in my household who let their lord be treated with such shameful contempt by a low-born clerk!"

It's not clear whether he specifically ordered retribution, but his furious outburst prompted four knights to travel to Canterbury in search of him.

Reginald FitzUrse, William de Tracy, Hugh de Morville and Richard le Bret all went on the search.

The assassination

There were five eye witness accounts of Becket's murder, but one account was written by Edward Grim.

He was so close to Becket when he was murdered, that he was wounded by one of the knight's swords.

As the knights arrived at Canterbury Cathedral, Grim recounts, Becket was in the Archbishop’s Palace and the four attempted to arrest him, but Becket resisted.

He was then persuaded by the monks to take refuge in the church, but the knights pursued him, bursting into the Cathedral with swords drawn.

They terrified people by shouting: “Where is Thomas Becket, traitor to the king and the kingdom?”

It was at this point the knights rushed at Becket.

They dragged him towards the doors, intending to kill him outside the church or carry him away in chains.

Grim's recount recalls Becket clinging on to a pillar in the Cathedral to prevent the knights from arresting him.

It was at that point one of the knights raised his sword and brought it down on Becket.

The blow sliced off the crown of his head and then two other knights started attacking him.

The monks who were there were so frightened they fled as a third blow brought an end to Becket's life.

The four knights had been joined on their mission by a clerk who became known as ‘Mauclerk’ or ‘evil clerk’.

Following the attack, Mauclerk is said to have "put his foot on the neck of the holy priest and precious martyr, and, horrible to say, scattered the brains with the blood over the pavement".

“Let us go, knights”, he called out to the others, “this fellow will not get up again".

The aftermath

Following the harrowing murder, chaos ensued.

Becket's mutilated body stayed where it had fallen for several hours and some people were said to have dipped their clothing in his blood or collected it in vessels to take away in anticipation of his future sanctity.

After Becket spent the night on the high altar of the cathedral, he was buried by monks the next day in the crypt.

Rumours and reports then circulated of miraculous healings connected to the dead Archbishop.

And following pressures from the people of Canterbury, the monks then opened the crypt so pilgrims could visit the tomb.

An extraordinary amount of 'miracles' were then recorded and, in recognition of this, he was made a saint (canonised) by the Pope on February 21, 1173.

Becket being made a saint was one of the fastest canonisations in history and his reputation as a miracle-worker spread quickly across the world.

People from all over Europe started to flock to Canterbury in the hope they would be healed.

Pilgrims could also buy a mixture of his blood and water, called St Thomas’ Water, which was bottled and sold by monks in small lead vessels called ampulla.

Henry II, in a public act of penance for his involvement in the murder, visited Becket's tomb in 1174 and granted royal approval to Becket’s cult.

The Archbishop's death and subsequent 'miracles' transformed Canterbury Cathedral into one of the most important pilgrimage destinations in Europe.

In 1220 his body was moved to a glittering new shrine in a purpose-built chapel upstairs in the cathedral.

Geoffrey Chaucer famously captured the atmosphere of a pilgrimage to this shrine in his Canterbury Tales.

In death Becket remained a figure of opposition to unbridled power and became known as the quintessential defender of the rights of the Church.

As a result people can find images of his assassination across Europe, from Germany and Spain, to Italy and Norway.

And to this day Becket remains a European saint and his relics, apparently including some of his bone, can be found at Canterbury Cathedral where they were visited by people from across the continent until 1538.

That was the year when Henry VIII would label him a traitor, order his shrine to be destroyed and attempt to wipe him from history altogether.

That, however, is another tale for another feature at another time.

The Thomas Becket exhibition is planned to open at the British Museum from Thursday, April 22 to Sunday, August 22, if the country is out of lockdown.

To find out more about the exhibition and how to get tickets when they go on sale, click here.

To read more of our in-depth features click here.

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