London Mithraeum

Seven feet below Bloomberg’s European headquarters lies a piece of ancient history. Discovered by chance in the early 1950s whilst examining a London bomb site, archaeologists stumbled upon the remains of a temple to the god Mithras dating from the 3rd century. Lead archaeologist William Francis Grimes (1905-88) claimed the discovery “was in the nature of a fluke” since no one was expecting to find anything more than the remains of buildings destroyed during the Second World War. Now, over half a century later, the carefully preserved London Mithraeum Bloomberg SPACE is open to the public along with displays of remarkable Roman artefacts found on the site of one of the UK’s most significant archaeological revelations.

The Mithraeum in 2004 when reassembled at Temple Court

It is with thanks to the software company Bloomberg that the Temple of Mithras is in such a publicly accessible space. On discovery, the temple was originally dismantled and repositioned nearby, losing architectural detail through the inaccurate reconstruction. In 2010, when Bloomberg took over the site, they were determined to take responsibility for the Roman monument and return it to its original position. Liaising with conservation specialists, the temple was once again dismantled and recreated in the form of the original ruin as it appeared at the end of the excavation in October 1954.

Temple of Mithras in its setting in Roman London by Judith Dobie

Illustration by Judith Dobie

Built in approximately CE 240, the Temple of Mithras would have stood on the east bank of the River Walbrook, which now flows underground. Landing in Kent in CE 43, the Romans, under the leadership of the emperor Claudius (10BCE – 54CE), succeeded in their conquest of Britain. Shortly afterwards, they chose the banks of the River Walbrook as their main settlement due to its proximity and easy access to the River Thames. This area they named Londinium.

According to geoarchaeologists, the topography of the land was very different from its present state. The City of London was once a wooded area and the River Thames was much broader than it is today. Nonetheless, the Roman settlers were quick to build up their city with stone structures, including a forum or marketplace, an amphitheatre, public baths and temples. Whilst these earlier structures would have been constructed predominantly from timber and mud bricks, the later buildings of the 3rd century were much grander and made of stone, for instance, the Temple of Mithras.

As those who visit the London Mithraeum discover, the temple was not particularly big, measuring 18 by 8 metres. Although only the foundations of the building remain, archaeologists have determined to a degree of certainty the appearance of the original temple. Stretching almost the length of the Mithraeum is the nave, where it is believed temple rituals were conducted. Either side of the nave are two aisles (north and south) where presumably a congregation of around 30 sat. Separating the congregation from the central nave was a low sleeper wall, the majority of which still remains. Seven-disc shapes along these walls indicate where stone columns would once have been.

The Temple of Mithras faces in a vague eastward direction with an entrance at the west end. Opposite the entry steps is a rounded apse that would most likely have featured a statue of the god Mithras. A stone head was uncovered in 1954 that may have been part of this statue.

Throughout the Roman world, there are 100 known remnants of mithrea, the majority of which are a similar rectangle shape, however, there appears to be no evidence that the temples contained windows. As a result, lamps or torches would have been the only available light sources. Four small holes behind the statue plinth in the rounded apse may once have held lit torches.

Little else can be gathered from the temple remains other than it was one of many buildings in the area. A stone relief found close to the temple’s site was inscribed “Ulpius Silvanus”, which could potentially be the name of the original founder or, at least, someone who lived nearby.

Today, the London Mithraeum Bloomberg SPACE provides visitors with a multisensory experience, which uses light and haze to construct the shadows of the seven missing columns whilst the sound of footsteps, chanting and whispers echo the rituals of centuries ago. After the mysterious display, the lights go up so that the ruins can be seen more clearly.

Whilst it is impressive to view the architecture of ancient buildings, the London Mithraeum leaves as many questions open than it answers. Why was the temple built? Who was Mithras and why did people worship him?

Inside London’s temple of Mithras – Judith Dobie

Tauroctony (bull-slaying) statue from the Temple of Mithras

Almost everything that is known about Mithras is the result of historians’ interpretations. Mithras was a Roman deity but his exact origins are unknown. Mithraism as an ancient religion appeared in the first century BCE and continued to flourish into the first few centuries CE. It is believed, perhaps due to the size of the mithrea, that the religion was worshipped in small groups rather than as a mainstream belief.

Statues and carved imagery discovered during excavations represent Mithras as a young man wearing a Phrygian cap. In a scene known as a tauroctony, Mithras is typically shown killing a bull while surrounded by other figures and animals. The meaning behind these figures are widely debated amongst scholars and, as there are no written documents about the religion, no one will ever be able to determine the exact truth. There was, however, evidence of ancient graffiti on the walls of the excavated temple. These inscriptions have helped to paint a hazy picture of the ceremonies conducted in the Temple of Mithras. Latin words taken from graffiti scratched into the wall of a Mithraeum beneath the church of Santa Prisca in Rome make up the script of the chanting heard at the London Mithraeum.

Mithraism is often referred to as a “mystery cult” since the majority of their practices were kept secret from the rest of the world, hence no books. Apart from archaeological evidence and graffiti that suggests the members of the cult consumed chicken, wine and honey, and that their ceremonies involved incense and smoke, little else is known.

Some scholars believe that Mithraism merged with Judaism to create Christianity, whereas others suggest it was eradicated by the latter. Saint Paul, who is often referred to as the first Christian, was born in Tarsus, a major centre of Mithraism. It is, therefore, possible that Paul moulded the laws and rituals of Mithraism into Christianity. This, however, is merely speculation.

“It was in Tarsus that the Mysteries of Mithras had originated, so it would have been unthinkable that Paul would have been unaware of the remarkable similarities … between Christian doctrines and the teachings of Mithraism.”
– “The Jesus Mysteries” by Timothy Freke & Peter Gandy (1999)

The Temple of Mithras in London, or Londinium as it was then called, was abandoned by the early 5th century due to the collapse of the Roman government across the empire. For a century or so, the land along the River Walbrook remained uninhabited, resulting in the collapse of buildings, a build-up of debris and soil, and a gradually rising ground level. This is why the remains of the temple are so far underground. By the time the area was reinhabited, the temple was hidden from site and Mithraism was forgotten with Christianity becoming the more predominant religion in the country.

Since the return of the population to Londinium, the city has expanded and been built upon, ultimately altering the landscape forever. St Paul’s Cathedral became one of the major places of worship after it was founded in 604 CE. With new buildings on the rise, including the Tower of London, which William the Conqueror (1028-87) was responsible for, no one questioned what may have been around beforehand.

The Great Fire of London in 1666 added more debris to the land, hiding the Roman remains further underground. By the time the World War II bombings destroyed most of the buildings on the site in 1941, the street level was at least 9 metres above the earliest Roman deposits.

It is in part due to the build-up of debris that the remains of the Temple of Mithras survived. The waterlogged nature of the soil along the Walbrook valley, which contained very little oxygen, was excellent for preserving archaeological architecture and artefacts. When the initial excavations began in the 1950s, many items made from organic materials, such as wood and leather, were unearthed – items that rarely survive. In preparation for the construction of Bloomberg’s headquarters, further excavations took place, recovering more Roman finds than any other site in the City. In total, over 14,000 artefacts were recovered as well as 63,000 pieces of pottery and three tonnes of animal bone.

Amber carving of a gladiator’s helmet

Display of Artefacts

Roman coins

As well as the Temple of Mithras, the London Mithraeum Bloomberg SPACE displays a variety of the artefacts discovered beneath the feet of Londoners that once belonged to Britain’s Roman ancestors. Each object provides an insight into the lives of people in Londinium from the things they treasured to the things they wore and consumed. Digital tablets allow visitors to choose objects to explore in more detail.

Whilst the excavated animal bones are not on display, they suggest the types of creatures the Romans may have eaten, for instance, chicken. Nearby, the remains of workshops and a bakery were discovered, revealing further insight into the daily lives of inhabitants. Within the displayed artefacts are hooks and weights, which are the remains of ancient weighing methods. These may have been used in the bakery or similar shops.

The remains of buildings, including the Temple, help to explain the architecture of ancient constructions. Floors appear to have been tiled or in some cases decorated with mosaics, and roofs were composed of clay tiles (tegula). Overlapping tiles made the roof more durable and waterproof, an architectural feature that was often used in ancient Greece and Rome.

Hypocaust Diagram

The Romans were a long way off the central heating Londoners have today, nonetheless, they had their own methods of heating their homes. Roman architects used a system called hypocaust in which the floor was raised above ground level to create a space for hot air produced by a furnace to flow underneath.

Buildings were entered through thick, wooden doors, a fragment of which miraculously survives. This fragment is made from panelled oak and it is believed that one of the large iron keys discovered on the site may have been used to lock this particular door.

As mentioned, objects made from organic material, such as the wooden door, do not often survive. Other organic items that withstood the test of time are leather shoes, wooden combs and wooden writing tablets. The latter would have been coated in wax and etched into with iron styli, many of which have also been recovered.

Metal items are more durable, therefore, it is unsurprising that iron styli, iron knives – one with an ivory handle, copper bells and copper alloy brooches have survived in abundance. Brooches would have been used to hold garments together by both men and women and were probably nothing much to look at in comparison to the elaborate brooches that are made today. An amber carving of a gladiator’s helmet that is thought to have been worn as a pendant for decorative purposes, since amber was a precious and treasured material.

Domitian, AD 81 to 96. Silver denarius

The most prevalent artefacts from the Bloomberg site were Roman coins of which over 700 were discovered. Similar to present-day money, coins featured the profile of the reigning emperor. The majority of these coins were manufactured during the reign of Emperor Claudius, however, the rest have been identified as other rulers, for instance, Emperor Domitian (51-96 CE), the last member of the Flavian dynasty.

Interestingly, many of the recovered items were produced elsewhere rather than locally, suggesting that the Romans brought their possessions with them or traded with other countries. The quernstone used in the bakery or mill to grind grain was produced from stone sourced in Germany. Glass objects have been identified as Egyptian and some of the brooches came from central Europe. Mediterranean lamps were popular and it is thought the Roman Empire bought their olive oil from Spain.

Samian pottery was popular throughout the empire and many examples have been excavated in London. Also known as terra sigillata ware, the bright-red, polished pottery was made of clay and impressed with designs. Animals were a common feature in Roman art and some fragments of pottery and stoneware feature images of British hunting dogs, wild lions, deer, eagles and bulls, possibly representing Taurus. The bull also had a strong connection to Mithraism.

Londinium only had a population of 10,000 during the first couple of centuries, which is a mere handful compared with the 8.8 million that have made London their home today. Thanks to the discovery of the Temple of Mithras and the enormous range of artefacts, it is possible to imagine what the life of these first inhabitants may have been like. Many items were discovered at the bottom of an ancient well, implying that the Romans threw a lot of their things away rather than adopting the make-do-and-mend attitude that was popular many centuries later.

Unfortunately, no matter how much is discovered, historians will never know for sure the accuracies of their speculation, however, the findings remain an interest to the public. The London Mithraeum provides the opportunity to imagine life in London 2000 years ago as well as discover an ancient religion. Although visitors may leave with more questions than they arrived with, it is worth taking the time to appreciate and explore the remains of our ancient ancestors.

We may never know who Mithras was nor why he was worshipped, then again, who knows what may be discovered in the future? If the Temple of Mithras was hidden under the City of London for almost two millennia, what else could be hiding beneath our feet?

The London Mithraeum Bloomberg SPACE is free to visit, but to guarantee entry you are advised to book in advance. Opening hours are Tuesday – Saturday 10.00 – 18.00 and Sundays 12.00 – 17.00.

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