The Celts: were they friends or foes of the Romans?

“Many Italian merchants, with their usual passion for money, look on the Gallic craving for wine as their treasure,” he wrote. “They transport the wine by boat on the navigable rivers and by wagon through the plains, and receive in return for it an incredibly high price.” Then, with thinly veiled incredulity, Siculus added: “For an amphora [a wheel-thrown terracotta container that typically held around 20 litres of liquid] of wine they get in return a slave – a servant in exchange for a drink!”

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It will come as a shock to absolutely no one to learn that human beings were every bit as likely to succumb to the temptations of drink 2,000 years ago as they are today. What many people will find more surprising about Siculus’s words, however, is the picture they paint of relations between the Romans and their Celtic neighbours – one in which the two peoples were engaging in trade, rather than hacking each other to pieces.

In the popular imagination, the Celtic-speaking people of western Europe were constantly at war with the Romans. The truth was very different. There were battles, of course, and the relationship would eventually end in bloodshed and subjugation after Julius Caesar launched his campaigns of conquest in Gaul in 58 BC. But the violence was preceded by long periods of peace and collaboration, and that collaboration benefited both parties.

Siculus clearly thought that the Gauls were being duped by wily Roman traders. After all, in Rome a Gaulish slave would fetch five or six times the price they could command at home. But Siculus was missing the point. In Gaul, slaves were available in surplus, a result of raiding between rival tribes. Once an external market developed for slaves, raiding could be intensified to satisfy the demand. A Gaulish leader could then offload surplus slaves in return for Roman wine that, distributed to his followers, would greatly enhance his status. For the chief, then, it was a very good deal indeed.

The Roman merchants were also doing very nicely out of their trading links with the Gauls. By the late second century BC, the Roman economy was changing dramatically. Small farms were being bought up and merged into vast estates run for their aristocratic owners by managers commanding armies of slave workers. The easiest commodity to produce on the slave-manned farms was wine. But as the estates grew and became more reliant on grape monoculture, wine production began to outstrip Italian demand. For the estates in western Italy, the solution to the problem was simply to ship the surplus to the major ports of southern Gaul – Massalia (Marseilles) and Narbo (Narbonne) – where middlemen were ready to transport it to the Gauls. The slaves acquired in return were brought back to labour on the estates. It was a system that benefited everyone – except, of course, the slaves.

As Roman estates became more reliant on grape monoculture, wine production began to outstrip demand

Roman expansionism

Rome’s involvement in southern Gaul can be traced back to the second century BC in the wake of the Roman army’s invasion of Spain. Troops and supplies now had to be dispatched overland to the Iberian peninsula, but these were vulnerable to raids by Gaulish tribes. So, to protect their supply lines, the Romans created the province of Transalpina, incorporating the entire coastal zone between Italy and Spain. (This eventually extended inland, west to the valley of the Garonne and north along the Rhône to its confluence with the Saône, and up to Lake Geneva.)

Under Roman government, Transalpina provided a comparatively safe base from which Italian merchants could operate. The province also provided a platform from which these merchants could establish amicable arrangements with neighbouring tribes beyond the frontiers – the Sequani, the Aedui and the Arverni. Although there was tension, for about 60 years (121–59 BC), trade between Rome and the Gauls flourished.

It’s difficult to estimate with any precision the volume of trade flowing between Rome and Gaul. But the number of shipwrecks found off the Gaulish coast surges after 150 BC, peaking at about 100 BC. This suggests an exponential rise in the volume of trade over that half century.

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For the most part, the vessels’ cargos were dominated by wine. The Madrague de Giens wreck was carrying around 7,000 amphorae when it sank off Hyères (south-eastern France) in about 50 BC. The quantity of amphorae discovered on the wreck suggests that the annual export of wine to the Gauls had reached about 100,000 hectolitres a year by the first century BC – a volume that would have generated about 40 million amphorae over the century. It is hardly surprising, then, that the Roman stereotype of a Gallic man was of a drunkard slurping wine through his long, drooping moustache.

The wine was transported along two major trade routes. One started at Narbo (modern-day Narbonne, founded in 118 BC), snaked along the river Aude and then overland to Tolosa (Toulouse) on the Garonne. The other travelled up the Rhône to Cabillonum (Chalon-sur-Saône) in the territory of the Aedui.

From these major transhipment centres, the wine was then taken into Gaulish territory to the principal settlements within easy reach of the frontier – places such as Bibracte, Jœuvres, Essalois and Montmerlhe. Roman traders may well have been resident in these native centres to oversee the exchanges. There were certainly Italian merchants in Cabillonum as late as 52 BC. These men were charged with ensuring a steady flow of slaves to markets in a bid to meet the Roman estates’ demand for a staggering 15,000 Gaulish slaves every year.

Cultural exchanges

Slaves and wine weren’t the only commodities exchanged by Roman and Gaulish merchants. The Romans sold olive oil, tableware, bronze vessels and jewellery. The Gauls supplied metals and cured hams.

These products greased the wheels of an increasingly productive relationship between the two peoples. Treaties were agreed, neighbouring tribes began to adopt Roman-style systems of government, and young Gauls served as auxiliaries in the Roman army. It’s a far cry from the stereotype of violence, conquest and subjugation.

In fact, such was the impact of these trading links on Gaulish society that it wasn’t long before Rome’s influence had drifted north across the channel into the British Isles. Britain was connected to the continent by a network of sea routes of great antiquity. Its inhabitants – although mostly Celtic-speaking like their neighbours – were referred to as Britons, not Celts, by classical sources.

The Greek explorer Pytheas had visited Britain in about 320 BC and his book, On the Ocean, was used as a source by later writers wishing to discuss these remote northern regions and, most especially, the trade route by which Cornish tin was transported by sea and river to the Mediterranean.

Julius Caesar needed a commission that would enable him to acquire enough booty to pay off his debts

Figs, coloured glass, metal tableware and wine were all transported to Britain. The wine was first taken to Armorica (Brittany), where it was probably exchanged for tin. Some of it was then transported across the peninsula to the north coast, and then shipped across the Channel to the British port at Hengistbury Head (now in Dorset).

In return, the Armorican middlemen acquired scrap gold, armlets made of shale, and probably grain and hides. The Greek writer Strabo, writing in the first century, also includes among the British exports slaves and hunting dogs (although they have left no archaeological trace).

The large quantities of Armorican pottery found at Hengistbury suggest that, along with Italian wine and other exotic goods, the Armorican traders also carried local products in their cargos – probably honey and other foodstuffs. They likely stayed in the port for the summer months, negotiating deals with the locals while waiting for ships to arrive from other parts of south-west Britain bringing metal ingots, as well as perhaps hides and slaves. When the haggling was done and the feasting was over, they returned to France.

So, from Hengistbury Head on the Dorset coast to Marseille on the banks of the Mediterranean, over the course of six decades from the end of the second century BC, the Romans and Celts established a trading relationship that brought both sides prosperity. Unfortunately, that relationship was highly vulnerable. In the face of two destabilising forces that exerted themselves upon western Europe in the first century BC, it was destined to turn spectacularly sour.

The first factor was population pressure. This had built up in the north-east when Germans from across the Rhine began to raid south, and the Helvetii tribe, living in what is now Switzerland, migrated en masse to the west. The prospect of Germans occupying the Alps was a cause of concern to the Roman elite, not least because migrating German tribes had menaced Rome 40 years earlier. These concerns were to play into the hands of the second destabilising force, Julius Caesar.

Caesar seizes the moment

In the mid-first century BC, Caesar was an ambitious young aristocrat who had got himself heavily into debt and had powerful enemies. Caesar needed a commission that would offer him the chance of military success to win him popular acclaim and to enable him to acquire enough booty to pay off his debts. His chance came in 59 BC when he forced through a law that gave him command of Cisalpine Gaul (in the north of the Italian peninsula) and Illyricum (which ran along the Adriatic Sea).

The following year, capitalising on the threat supposedly posed by the migrating German tribes, Caesar led his army through Transalpina and into free Gaul, spearheading a campaign of conquest and destruction. By 57 BC his armies were involved along the entire Channel coast, from the estuary of the Loire to the Rhine. Caesar spent much of 56 BC subduing a rebellion among the Armorican tribes, culminating in a great sea battle in Quiberon Bay off the south coast of Brittany. Realising that the rebels, with their maritime tradition and close links to Britain, remained a potential threat, Caesar acted with characteristic decision: “I put all their elders to death and sold the rest into slavery.”

After eight years of campaigning, the Roman general had conquered the whole of Gaul and had enthralled his countrymen by crossing the Rhine into Germany. But he wasn’t finished yet. In 55 BC and 54 BC, Caesar led two campaigns into Britain, crossing to Kent and moving on to bridge the Thames. During his campaigning in 54 BC, Caesar sided with Mandubracius of the Trinovantes tribe against his rival, Cassivellaunus, ultimately forcing the latter to acknowledge subservience to Rome by giving hostages and agreeing to pay an annual tribute. A few years later, entrepreneurs from northern Gaul began to develop a lucrative trading network with the pro-Roman tribes of south-east Britain. It may even be that the Trinovantes exercised a monopoly over trade with Roman Gaul.

Caesar eventually withdrew from Britain. And, once the legionaries had retreated, trade between the Romans and Britons flourished – just as it had done between Romans and Gauls – for 90 years (54 BC–AD 43). In one of his odes, the poet Horace, writing around 15 BC, listed British chiefs among those who “admired” and “heard” the emperor Augustus. A decade or so later, Strabo could write that the Britons “submit so easily to heavy duties both on exports from there to Celtica [Gaul] and on imports from Celtica, (these latter are ivory chains and necklaces, and amber gems and glass vessels and other pretty wares of that sort) that there is no need of garrisoning the island”. In other words, trade was so beneficial that it was in both parties’ interests that controlled commerce proceed unhindered.

Luxury goods now flowed into south-east Britain – much of this is known now from the commodities chosen to be buried with the British aristocracy. Wine featured prominently, but was now accompanied by olive oil and fish sauce from southern Spain, together with bronze and silver table wear, glass gaming pieces and jewellery. The British elites were regularly defining themselves by their ability to embrace the Roman lifestyle. The British king found buried in a tomb at Lexden in Essex even carried a medallion depicting the head of the Emperor Augustus – a prize possession perhaps received as a diplomatic gift.

But history was about to repeat itself. In AD 43, like Julius Caesar before him, the Roman emperor Claudius ordered his legions on a campaign of conquest in northern Europe in a desperate bid to attain military glory. And so the invasion of Britain began. Like their Gaulish cousins before them, the British were to discover that the era of mutually beneficial collaboration between Celts and Romans had come to an end.

Barry Cunliffe was formerly professor of European archaeology at the University of Oxford. His books include The Ancient Celts (OUP, 2018).

Culture clashes: 4 ways in which the Romans and the Celts differed

ROMANS

Gods

The Romans had a distinct pantheon of deities. Religion was part of daily life in Rome and each home had a household shrine.

Languages

Many languages were spoken in the Roman empire, but Latin was the official language of administration and writing.

Food & drink

The Roman (Mediterranean) diet was based on wine and oil. Cereals were widely eaten, but the wealthy had access to a wide range of meats, fishes, vegetables and fruits. The Romans used many ingredients familiar in modern Italian cuisine, ranging from olives to carrots to figs.

Dress

Roman dress varied considerably with status and occupation, but generally involved loose-fitting clothing, as befits a hot climate.

CELTS

Gods

The Gauls and Britons also had many gods. However, broadly speaking, they were divided into two types: deities of the Earth, usually female and often associated with springs; and tribal deities, often of the sky and usually male.

Languages

The Gauls and Britons spoke various dialects of Celtic, although the Belgae of northern Gaul, and possibly some of the people of eastern Britain, may also have spoken a Germanic language.

Food & drink

The diet of Gauls and Britons was based on beer and milk. They also ate cereal and tucked into meat as a supplement, particularly at feasts. This meat included game such as deer and wild boar, but they also slaughtered domesticated animals.

Dress

The Gauls and Britons probably wore tighter-fitting clothes, including trousers that were tied with leather belts and shirts that were similar to tunics.

This article was first published in the Christmas 2018 edition of BBC History Magazine