At the end of the last Ice Age the world warmed and the glaciers melted. Large volumes of water flowed from Britain, south and east, through what is now the London area, which at times would have been completely submerged by a very wide river. The rising water level formed the English Channel, separating Britain from the Continent. The wide, slow-moving Thames deposited gravel at its edges. As it narrowed and became smaller over thousands of years, its gravel-depositing edges moved inwards in an ever-lower series of terraced banks, and thus the youngest layers lie closest to the current banks of the river and the oldest further away on the valley sides. Many rivers and streams flow into the Thames from the higher ground to the north and south and erosion from those during the past 50,000 years created the many valleys around which London was later built.
In 54 BC Julius Caesar led his army across the Channel to Britain to subdue the native Catuvellaunian tribe. Yet having beaten them back he decided there were more pressing issues and swiftly returned to Gaul. Back in Rome, he later recorded his campaign against the British ‘whose territories a river called the Thames separates from the maritime states at about eighty miles from the sea’. We therefore have the earliest record of the river, written long before the establishment of the city through which it now flows.
Tiberius, a strong military leader, secured the Roman Empire’s northern Continental borders. After his death the nobles who controlled the Senate in Rome became tired of their new young Emperor Caligula’s pleasure-seeking and longed for imperial glories such as the legendary exploits of Julius Caesar ninety years earlier. Caligula thus attempted an invasion of Britain in 40 AD but his troops, assembled at Boulogne, had other ideas, and it seems they threatened to mutiny. Britain, to the ordinary soldier, was a mysterious place at the far edge of the world, where boats carried the souls of their dead crews. The British were to be left alone for another three years.
Following the assassination of Caligula, his uncle, Emperor Claudius, felt the need to spread and reduce the power of the armed forces by sending 40,000 soldiers to the mysterious island, so the Romans finally arrived and conquered Britain. It took Commander Aulus Plautius and his troops a short while to actually find any Britons with which to engage but once located they were pursued across the Thames. Having taken the south-east corner of Britain, Plautius set up a ‘marching camp’, probably on the north bank of the river at Cornhill, waiting for the Emperor to arrive with reinforcements. Claudius came with a large reserve force, together with elephants (according to a later Roman account) that no doubt gave the natives a huge fright. The imperial army moved on to the main Catuvellaunian stronghold at Colchester, which the Romans took without too much difficulty. Claudius received oaths of loyalty there from eleven tribal kings and then returned home after just sixteen days, leaving his troops to set up the capital of the new Province of Britannia.
For the Emperor and so many troops to reach Colchester, as well as maintain supply lines back to Gaul, a bridge was required across the Thames. The first crossing was most likely a temporary pontoon structure put in place by army engineers. The Romans found the best location was just downriver from where the Thames was joined by the River Fleet. The banks of the Thames were quite marshy and the chosen site probably the most easterly, or downriver, point at which the river was sufficiently narrow, with solid land on either side.
When the Romans arrived, what is now central London was an area of small hills surrounded by marshy land that was often flooded by the incoming tides. The Thames was then the border between different warring tribes. The wider London hinterland, with its poor clay soil, remained forested and largely unpopulated, being far from each of the main tribal capitals. The thick forests and marshes on each bank made the river a natural barrier between the different groups of people that lived to its north and south but also a better means of transport and trade than overland.
Despite there being surprisingly little contemporary written evidence of the Roman city of Londinium, much has been pieced together by historians. There was a great deal of uniformity across the Empire, which allows an understanding of Londinium through discoveries made elsewhere. More locally, the remains of a Roman ship were discovered on the Thames in 1910 and two more in 1958 and 1962. After the Second World War many of the buildings in the City of London, particularly along the riverfront, were redeveloped and this gave the opportunity to delve below, before the replacement buildings were constructed. In the early 1970s a systematic programme of archaeology started and discoveries began to be made. Gradually, piece by piece, an understanding of the Roman Port of London emerged. Similarly, the existence of the Saxon town of Lundenwic was only revealed following excavations at Jubilee Market at Covent Garden in 1985.
The foundation and growth of Londinium
As the Romans established a new provincial capital at Colchester their forces moved northwards to continue the advance through Britain. In order to hold the areas they had conquered, one of their first priorities was to build wellengineered roads so that troops could move swiftly and have a means of supply. By the time they arrived in Britain the Romans were masters of rapidly building good roads and in the first years of occupation they constructed a network in the south east of Britain, partly based on native tracks that existed before their arrival.
A number of those roads connected at points to the north and south of the Thames bridge. The original temporary military crossing was probably soon replaced by a more permanent structure, thought to be located in line with the modern Fish Street Hill, slightly downstream of the current bridge. Such an important point required a military guard and a certain amount of management to supervise traffic and make repairs, so a small settlement was established on Cornhill. It soon became clear that a larger presence, formally constituted, was required on the site. The decision to build the new town of Londinium on the north side of the bridge was taken in around 47 AD and building works started the following year. A commercial district of shops and workshops evolved along the Via Decumana, the modern-day Cheapside. It quickly grew into a busy conurbation, home to people from all parts of the Empire but probably mostly from Gaul. The population increased rapidly and by 60 AD it is estimated to have been in the region of ten to twenty thousand people.
Londinium enjoyed a favourable location. A long navigable tideway brought vessels fifty miles from the North Sea, providing relatively easy access from Continental Europe. There was fresh water, fish stocks, and rich agricultural land further upriver. The first town lasted for little more than a decade before being destroyed and reduced to ash during Queen Boudicca’s rebellion. It had by then become an important and strategic place so had to be restored. Its destruction gave the Romans the opportunity to rebuild on a grander scale. During that same period a decision was taken that Londinium should become the capital of Britannia in place of Colchester. In the latter first century a vast basilica, the administrative centre, was constructed. Various government and public buildings were established, many in Kentish ragstone brought up the Thames by boat from a quarry near the River Medway. By the end of the century Londinium was beginning to look like the type of Roman town we would usually imagine. At some time between 85 and 90 AD a new bridge was built over the Thames, constructed of wood. The city continued to evolve and expand in the second century, particularly at the time of the visit of Emperor Hadrian in 122. Many public buildings were rebuilt for the occasion, including the amphitheatre, and a forum (marketplace) was created adjoining the basilica.
At some point during the period between 190 and 210 a semi-circular wall was constructed around the land-facing sides of Londinium. It was a massive undertaking, requiring around 1,300 barge-loads of ragstone from the Medway. It was not put up in haste, probably taking around two years to construct, and did not protect the vulnerable riverside, indicating that the city was not under immediate threat of attack. The existence of the wall thereafter created a barrier to further outward expansion of Londinium, which remained the case until the Middle Ages.
Initially many of the town’s daily requirements were imported but as time went on workshops were established to produce goods for the resident population. The remains of mills, slaughter houses, and a glassworks have been discovered as well as many tools for metal-working, carpentry, engineering, building and shipping. Britain was a major source of wool and it is most likely that the city was a centre of textile and leather industries.
The staple food of Roman times was cereals and bread, which depended on the seasonal harvests. Occasionally riots occurred in various parts of the Empire when availability was scarce and prices high, so each town arranged warehouses where grain could be stored in plentiful years. Londinium had the disadvantage of being surrounded by poor farmland so grain had to be transported lengthy distances, much of it arriving at the Thames quays by boat from Buckinghamshire, Oxfordshire and along the River Lea.
Fish was plentiful and could be caught in the river and estuary. Varieties included herring, cod, sprat, eel, carp and bass. Oysters were a staple diet of both the wealthy and working people. The largest oyster beds in Britain were in the Thames Estuary and the shellfish were either brought upriver live in barrels of sea-water or pickled and stored. Fish and shellfish were usually eaten with garum, a sauce made by boiling down whole fish until it became a paste, after which it could be stored in jars and sold in shops. A factory where it was made seems to have operated close to the Londinium waterfront. British oysters were exported to other parts of the Empire and their shells have been found in excavations of Rome. Salt was brought to Londinium from inland mines or by boat from around the coast, particularly from Essex where it was extracted from water using pans.
By the third century the population of Londinium is estimated to have been at least 50,000 and perhaps as much as a 100,000 people, a number that would not be achieved again until the fourteenth century.
The main Roman trade routes from the Mediterranean to Londinium
The port of Londinium
Even before Londinium had been established, the invading army created a supply base at Richborough in Kent, north of modern-day Sandwich, which in those days was a natural harbour. Its closeness to the coast of Gaul ensured that Richborough continued as a port throughout the Roman period, particularly for larger vessels from southern Europe. From the first until the late third centuries it was, along with Dover and Boulogne, a base of the Classis Britannica, the division of the Roman navy entrusted with the security of the English Channel.
Roman ships generally only sailed to Britain in the calmer weather of the summer months. The open sea was avoided whenever possible, with ships hugging the Continental coast until able to take the shortest possible route across the Channel. Goods from the Mediterranean were generally shipped to Britain via the inland Rhône-Rhine route, rather than around the more exposed Iberian Peninsula, and transhipped at Domburg in the Netherlands. From there the sea journey from the Rhine estuary to Londinium was around thirty-six hours so, with turn-around time, a ship could make three or more voyages each fortnight. An alternative route, particularly for goods originating in central Gaul, was along the Rhône and Loire rivers and up the west coast of Gaul.
Navigating up the Thames from the North Sea was always slow and difficult for sailing ships. First they had to negotiate the many sandbanks along the north and south shores of the Estuary, then wait for incoming tides to sweep them up to Londinium. The prevailing wind is more often westerly than from the east and thus the going could be slow as the crew tacked their way upstream along the winding river. It was therefore more convenient for goods arriving on larger vessels to be reloaded onto smaller vessels at Richborough. From there they were brought up the Thames to Londinium or transported by road.
In the first decade or two of the settlement of Londinium boats, were most likely berthed on a sloping prepared beach. The first attempts at establishing a harbour were probably not made until the rebuilding of the town following the Boudicca rebellion. In around 62 AD new timber quays and warehouses were constructed, perhaps at the same time as a new bridge. They included a landing stage for small vessels, parallel to the bank. The work was almost certainly a public, not private, initiative and probably undertaken or supervised by military engineers. To the west of the bridge the waterfront buildings seem to have been residential whereas those to the east formed commercial wharves. Quayside warehouses of timber may have been constructed in the first century and later replaced by others built in stone.
By the end of the first century the original quays and landing stage had been replaced. In those times the Thames was much wider than today, possibly as much as one kilometre across at Londinium, with marshy islands on the south bank that became submerged by high tides. The quays were built out into the river, gradually advancing the waterfront terrace by around fifty metres in various stages of development between the first and third centuries. This advancement would have provided berthing in deeper water for larger vessels.
Initially Londinium probably acted as a supply hub for Roman Britannia, with goods and equipment passing through for the military campaign and the first wave of Roman occupiers. As Londinium grew, other towns were also established, with over forty Roman coastal harbours known to have existed to which goods could be shipped. Food, manufactured goods and luxury items continued to be imported into the capital from all parts of the Empire but by the early second century produce arriving was simply to meet the daily needs of the city and its immediate hinterland. The harbour was to remain relatively small compared with the great ports of Portus and Ostia that served Rome.
Many goods landed at Londinium came from northern and central Gaul, the Rhine ports and Bordeaux, but there were also some from Spain and Mediterranean harbours and North Africa. Certainly sculptures, bronzes, household goods and foodstuffs that have been unearthed in Londinium were of Italian, Spanish or Mediterranean origin. Olive oil for cooking and lighting came from Spain, wine from Gaul, the Rhine and Moselle areas, Italy and Spain. Other imports included textiles, silk, linen, quernstones (millstones), timber, pottery, samian crockery, glassware, lamps, jewellery, fish, fruit, honey, grape-syrup and salt. Garum came from Gaul and Spain, at least until it was manufactured in Londinium. Most cargoes arriving from long distances would have been transhipped several times through the extensive Roman entrepôt network on their journey. Ragstone and other kinds of stone were quarried locally in Britain and shipped to Londinium by river or around the coast, as were locally produced ceramics and roofing slates in the second and third centuries. There is less information regarding exports from Londinium but they are known to include capes, rugs and lead ingots. Most likely other exports were wool, grain and slaves.
As is known from other parts of the Empire, goods were carried in sacks and barrels. Liquids, such as olive oil, were transported and stored in pottery storage vessels known as amphoras that could be stacked upright or horizontally. Unloading a Roman vessel was labour-intensive and, as it was seasonal work, probably required a casual workforce. It is possible that lifting mechanisms were used to unload larger items but there is so far little evidence. As boats arrived, some goods were probably sold directly to the public on the quayside while others were put into transit buildings or stored in warehouses.
Sea levels in the first century were about three to four metres lower than today. There is evidence that the Thames was then tidal perhaps as far upriver as Westminster, but may have gradually receded during the Roman period in one of the world’s slow cycles of climate change. If that is the case, vessels could no longer be swept up as far as Londinium on an incoming tide. That would be a significant factor in the decline of the city in the late Roman period.