Historical Overview

The Arrival of Rome: Conquest, Resettlements and New Horizons

The origins of Roman Bonn are a product of military conquest, led by who is probably the most famous of Romans, Julius Caesar. From 59 B.C., Caesar was governor of the Roman province of Gallia Transalpina (today, Southern France) and expanding Roman, and his personal, power north. This also brought him and his legions to the Western bank of the Rhine, ostensibly to help allied Gauls living here against the raids of people from across the river. 

We owe to Caesar – who later commemorated his military activities in his famous Gallic Wars – the dictum that the Rhine divided Gallic and Germanic populations. We know such ethnic labelling and division also from later forms of imperialism as a measure of control, and it gave Caesar justification to intervene in local conflicts. In reality, there was much exchange between people across the Rhine, both violent and non-violent. And not everyone, especially on the lower Rhine, was happy with the arrival of Romans either. Between 57 and 51 B.C. Caesar fought a brutal war against an alliance of “Gallic” and “Germanic” people which saw hundreds of thousands of people killed or enslaved. Among them were the Eburones who lived in the region between what is now Bonn, Cologne and Aachen (the Kölner Bucht). Under their leader Ambiorix they had dared to ambush and destroy a Roman legion when Roman need for supplies threatened their winter rations. We should always remember the massive dangers that such large-scale military occupation brought to a world of largely subsistence economy. After this, the Eburones disappear from history. Caesar writes that he destroyed “the stock and name of the tribe” (Gallic Wars 6.34) which has led some historians to describe his actions as a “genocide”. From archaeology we know that the Gallic wars left the region in which later Bonn would be situated deserted.

In 50 B.C., Caesar returned to Rome, leaving behind an unsettled situation. This was why about a decade later, another governor of Gaul, Marcus Vipsanius Agrippa (best known for building the Pantheon in Rome), decided to resettle the “Kölner Bucht” with local people friendly to Rome. These were the Ubians, who had previously lived on the Eastern side of the Rhine opposite what is now Koblenz. They were, by Roman interpretations, “Germanic”, but their resettlement also shows that, when it suited Romans strategically, the cultural paradigm that these should stay on the East side of the Rhine was disregarded. The Ubians would become the local population in the “Kölner Bucht” and therefore also in Bonn. 

Bonn, or rather Bonna, itself is for the first time mentioned between 13 and 9 B.C. by the Roman historian Florus (Florus, Epitome 2.26; though here it is spelled Borma). The name might be of Celtic origin. It was the site of a wooden Roman auxiliary fort, probably situated on what is now the Belderberg near the opera, which served as part of the military operation Romans conducted across the Rhine in this period. That military operation ended in disaster, when, in 9CE, three Roman legions were defeated by a coalition of peoples living in what is now north-western Germany in the so-called Battle of the Teutoburg Forest. Following this, Romans built up the lower Rhine as a military chain, linking three legionary forts, in what is now Nijmegen, Xanten and Bonn. The fort in Bonn, dating to the 40s CE., was situated on a plateau opposite the estuary of the Sieg. First, it was a wooden building, but in 70 C.E. it was rebuilt in stone after it had burned down during the Batavians revolt, a rebellion of local auxiliary troops in the unsettled period following the death of the emperor Nero. 

The legionary fort, first housing the Legio I Germanica and from 83 C.E. the Legio I Minervia as well as auxiliary troops, became the focal point for the region for the next three-hundred years. Its impact on this previously sparsely populated iron-age landscape must have been enormous: alongside military personnel of c. 7000 people, most of whom would retire in the vicinity, we must count the large numbers of civilians it attracted to its environs. In Bonn, we know of settlements just outside the fort (the so-called canabae legionis, where also the families of soldiers lived) and of a large town-like settlement (vicus) just upstream, around what is now the Gronau. Up to 10,000 people might have lived here, engaging in the crafts and trades needed to sustain the military presence. Between soldiers and civilians, people came from all over the empire, and from as far afield as Thrace (modern-day Bulgaria), Ankara or Petra in Arabia. Local economies and cultural habits were profoundly transformed, a process that brought opportunities but also the loss of local people‘s histories.

Soldiers and Citizenship 

After the integration of the lower Rhine region into the Roman empire, new elites began to emerge. They were now distinguished by Roman citizenship, a set of rights that allowed people to trade, marry, pass on their property and settle disputes protected by Roman law. First among those holding Roman citizenship were the legionary soldiers, for only those with Roman citizenship could serve in the legions. We would be mistaken however to think that these all came from Rome: Roman citizenship was not an ethnic marker, but a legal privilege that could be conferred on people from across the empire, some of whom may have never been to Rome. A case in point may be the legionary soldier QUINTUS PETILIUS SECUNDUS who came from Milan and was buried in Bonn in 65 C.E. (see the inscription). He had been a soldier of the Legio XV Primigenia stationed in Xanten and had sadly died at only 25 years of age, after only 5 years of service. It is unknown why he was buried so far from his workplace, but it is clear that those who installed his tombstone wished to celebrate his superior status. They did so by showing him in his military attire, with mantle, short sword and spear reserved for legionaries, but also via the inscription chiselled into the stone. Here they declare themselves his “heir” alluding to Roman testamentary practice, give Secundus’ full three-part name that only Romans were allowed to carry, his filiation (son of Quintus), an important sign of belonging in the patriarchical Roman world, and, crucially, his voting tribe (Ufentina). During the Roman republic, all Romans were enrolled in such tribes so they could vote in the popular assembly in Rome. By the time of Secundus this had become meaningless, not only because now there were Roman citizens all over the empire who could not be expected to travel to Rome to vote, but also because political participation of the people had ceased. Now, it simply signified social distinction.

In addition to soldiers who bore Roman citizenship, many non-Roman citizens also served in the Roman army as so-called ‘auxiliaries’ and were stationed in Bonn. One such example is known to us thanks to an inscription found somewhere along Adenauerallee, bearing the the following text: Reburrus Fra/tton(i)s f(ilius) eques al(ae) / Fr[o]nt(onianae) / “Reburrus, son of Friatto, cavalryman of the Ala Frontoniana.”

This inscription, plus one other found alongside it, is the basis upon which the auxiliary units that are now believed to have been stationed in Bonn were determined. Namely, the Ala Frotoniana and the Cohors Prima Thracum Germanica. These were stationed in a separate auxiliary camp which has now been shown, thanks to archaeological excavations in the 1980s, to have been based at the eastern end of the modern city center, broadly in the vicinity of the modern opera house. This has been confirmed through the excavation of the remains of wooden-and-earthwork fortifications as well as trench systems and the remains of troop barracks. 

Some scholars have suggested that Reburrus may have been recruited in the reign of Tiberius and perhaps died in the reign of Nero. The inscription is probably therefore probably datable to between approximately 50–70 C.E. 

Reburrus’ unit, the Ala Frontoniana, was probably raised by Augustus or Tiberius in Gallia Belgica, the province immediately to the west of the one in which we are based now (Germania Inferior), situated in what is today Belgium. Auxiliary units were raised from subject provincials in regions conquered by the Roman Empire who did not hold citizenship (peregrini), which, as has already been mentioned, was a requirement for entry into the legions. After 25 years’ service in this period an auxiliary soldier would receive citizenship, so such units served as mechanisms for the integration of subject provincials into Roman society. This situation changed after 212 C.E., when citizenship was extended to all free inhabitants of the Empire by the Constitutio Antoninia, a change which would later come to have drastic ramifications for mechanisms of Roman military recruitment, and the role which the military played in the governance of Roman society.  

The term ala, meaning ‘wing’, has its roots in the the term which was used for confederate allies of the Roman Republic in Italy in the centuries before Augustus’ establishment of the Empire, and which serve as a clear inspiration for the organisation of these units. In Reburrus’ day, alae were elite calvary units, typically armed with a spatha, a form of longsword which provided much greater reach than a legionary soldier’s gladius, but in late antiquity the spatha would develop to become the Roman army’s standard infantry weapon, and became associated with Germanic-speaking soldiers from beyond the Rhine who had been recruited on the Empire’s military frontier. 

The number of auxilia serving in the Roman Army under Tiberius is believed to be roughly equal to that of the number of legionaries. The Roman army was thereby heavily reliant on such soldiers, and it is important to emphasise such soldiers could usually be well relied upon. The ideology of their loyal service is well reflected in the iconographic features found on Reburrus’ epitaph, which show Reburrus in a triumphant stance riding down a barbarian foe — it is worth bearing in mind that such barbarian foes would have quite likely been his own co-linguists from the other side of the Rhine, whose shared language and barbarian roots seem to have led to no hesitation in depicting them as thoroughly alien. This is not to say that there were not were serious exceptions to this general reliability — we have already encountered examples such as the Cheruscan auxiliary commander Arminius’ revolt and destruction of three legions at the Battle of the Teutowald at the end of the first century B.C., or the revolt of the Batavians which devastated Germania Inferior (including Bonn) in the late first century AD. The Batavian revolt indeed seems to have prompted some serious changes in organisation — after this revolt auxiliaries were no longer stationed in their home province. Moreover, auxiliary commanders had usually themselves been barbarian elite nobility, and after the Batavian revolt such commanders seem to have no longer been allowed to command units raised from their own ethnic group.

The first part of the fortress was built early in the First Century C.E., and was located between Bertha-von-Suttner-Platz and the modern main university building, known to us through the remains of comparatively small camp probably associated with legionary and auxiliary units, for which excavated remains three metres wide were discovered during construction work for what is now the Dorint Hotel in 1983. This camp was refurbished at some point around the middle of the first century, as evidenced by an appropriate inscription. Suburbs for this camp extended further to the south towards the flood plains which are now the area between the town centre and Heusallee. 

The main camp was built in the area free from these flood plains. Between 30 and 40 C.E. the Legio I Germanica was relocated from Cologne to Bonn, at which point when much of the main camp was built, extending from what is now Rosental to the south and the Augustusring to the north, and Graurheindorfer Straße to the west. 

The original fortress which was largely timbered, but was rebuilt primarily in stone late in the First Century. It may have burned down immediately prior to this reconstruction, a possible consequence of the Batavian revolt, which affected much of the Rhineland and which forced the Legio I Germanica to abandon the camp. The reconstruction measures are attested by an inscription dating to 78 C.E.  

There have only been very few traces found of the wooden camp, and the best known part of the site to archaeologists is the later stone fortress. The building materials for this fortress were acquired south-west of here, in the Drachenfels, a range of substantial hills in the vicinity of Königswinter, that were also the source of building materials for other fortresses along the Rhine, such as as Xanten. When the river is low the remains of the Roman harbour in Königswinter where these stones were loaded are still visible from up in the hills. 

At 27.8 hectares (278.000 m²), the rebuilt fortress was among the largest in the Roman Empire, and its remains today form a key component of the modern UNESCO World Heritage site „The Lower German Limes“. Although the vast majority of it is not visible because it sits beneath the modern Castell district of the city of Bonn (to which the fortress lends its name), around 83% of its remains are in fact still intact, and a quick examination of a modern map of Castell shows that this part of the city follows the layout of the fortress quite closely (Rosental - Graurheindorfer Straße - Nordstraße - Badener Straße - Am Schänzchen). The fortification would have been divided into four quarters by two intersecting main streets — the via principalis, running north-south, along what is now Römerstr., and the via praetoria running east-west, along what is now Nordstraße. Each of these quarters would have been divided into three zones, known as ‘scamna’, by streets running parallel to the via principalis.  Where these intersect there would have been a main administrative building built out of stone called the principia. Housing for the various cohorts of the Legio I Germanica would have been spread out throughout this camp, with barracks for the cohorts around the edges and higher ranking officers residences closer to the principia, immediately south of which was the commander’s residence, the praetorium, in which the remains were found of pillars for a hypocaustum, for the commander’s private baths, as well as fresco mural paintings, a typical element of elite Roman interior decoration. The officers would have also had comfortable accommodation — an elaborate mosaic depicting the mythological figure Medusa was discovered in a building believed to be an officer’s residence, though this mosaic was destroyed by a bombing raid during the Second World War. Common enlisted soldiers also had access to amenities such as basins of water for washing. This would have been supplied from an aqueduct which entered the fortress at its southwestern corner supplying water from a source in the modern city district of Hardtberg, 11 km distant. The praetorium had a large courtyard with galleries surrounding it on three sides, and large great hall (‘basilica’) at one end, behind which the legionary standards would have been displayed. There was an enormous hospital (valetudinarium) in the north-western quarter. 

Buildings with a range of economic or productive functions were found inside the fortress, indeed around twice as many as would have been needed for the number of soldiers stationed here, which suggests that the camp served not just as a residence for the soldiers based here, but also as a quite important storage depot for the maintenance and supply of the entire army upon the lower Rhine. We know this from a series of building that were discovered in archaeological excavation toward the centre of the eastern end of the fortress. Here traces have been found of a storage warehouse, as well as four very large granaries, and an armoury and weaponsmithing workshop known as a fabrica, where archaeologists also found remains of worked and molten non-ferrous metal, there was another set of workshops or stalls, called tabernae, in which there was found evidence for glass and non-ferrous metal being processed in furnaces, alongside a range of other economic or industrial buildings. 

There was a very large port at the fortress, traces of which are still visible when the Rhine drops to a low level along the West Bank of the river between the Augustusring and Wachsbleiche, where one can see remains of a stone jetty. This would have been a significant port  for cargo-bearing ships, and much of the fortress’ supply needs would have been met from the river, including vast quantities of grain and other products brought to feed the soldiers from Britain, and wine and olive oil from the Mediterranean. The distribution networks for these supplies are well known to archaeologists especially thanks to the vast quantities of ceramic sherds as well as complete pots in which much of this produce was transported, and such remains have allowed scholars to conduct detailed studies of how trade networks changed over time in order to meet the needs of the Rhine’s inhabitants. Near to the location of the jetty, where the Augustusring meets Römerstraße, there is today a modern reconstruction of a Roman crane, of the sort which might have been used here, and is based upon depiction of such a crane in relief decoration from a funerary monument.

The population of Bonn in the 1st-3rd century C.E. can by no means be regarded as homogeneous. The relocation of the Ubians tribe to the left bank of the Rhine filled a void left behind by the Eburones. The Ubians settled and protected the border on behalf of the Romans. The auxiliary troops consisted of locally recruited soldiers, whereby a Roman administrative and military presence must also be assumed.

The legio I Germanica, which was presumably recruited by Caesar, and the legio XXI Rapax brought further non-local soldiers (most likely from Italy) to Germania inferior. Both legions had already been deployed in other areas of the Roman Empire. Due to the high mobility of the soldiers, it is not unlikely that they met women in other areas or bought slaves to accompany them on their expeditions. Even if the soldiers were not allowed to marry, their families would have settled in the suburbs around the camp (canabae legionis).

The long presence of the Legio I Minervia in Bonn led to a growth in the settlement around the legionary camp. The economic prosperity also attracted traders who benefited from the Roman road network. A votive stone for the Matronae, on which a man in a Roman toga and a woman in Ubian costume can be recognised, clearly shows that Roman and Ubian cultures grew together over the time. The exchange was certainly not one-sided, as the matronae were local deities who were also worshipped by commanders and Roman aristocrats, as numerous inscriptions prove. The cult is a recognisable example of how local and immigrant populations grew together.

The cult of the Matronae, which probably originated among the local population in Nettersheim in the Eifel, found its new centre in Bonn, where there was most certainly a large sanctuary for the Matronae Aufaniae. This may have attracted the population from the region, but the soldiers also carried the matrons with them on their campaigns and dedicated them at their respective locations.

A temple for Mercurius Gebrinius and the Mithraeum in Palais Schaumburg are evidence for the diversity of cult participants who combined Roman and local cults (interpretatio).

The expansion of Bonn can also be seen in the vicus located in the south of the camp, which archaeologists initially underestimated in size and whose existence was unknown until the end of the 20th century. Craftsmen, tavern keepers and aristocrats lived here with servants and, as the discovery of a mould for counterfeiting coins shows, criminals too. All the people living in the vicus could meet in the baths or when walking around the shops open to the street.

With the economic growth and rising importance of Bonn as a legionary centre, the diversity of the population will also have increased. This development will also have attracted labourers from the surrounding area to work on the estates (villae rusticae) that supplied the settlements. The mixture of Italic soldiers, foreign auxiliary units, resettled Ubians, migrant families, travelling merchants and attracted workers is reflected in sepulchral and religious inscriptions.

It is common to think of the Rhine frontier as a border separating civilisation from the wild barbarians beyond: Roman ideology very much encourages us to see things this way. It is perhaps more productive, however, to treat the Rhine as a major communication artery. This communication artery connected the entire network of settlements and fortifications along the Rhine frontier and likewise acted as a major transport and supply vector between the continent and the North Sea, especially in connection to Britain, which in the period of the later Empire acted as a major supplier of grain to the Rhineland procured through taxation. It also connected the Rhineland to the world beyond the Empire‘s borders, that is, the North Sea coasts east of the Rhine and and Scandinavia. This is archaeologically visible along the Rhine in containers of other products that ‚piggybacked‘ off of these shipments, such as the Black-burnished Ware manufactured in Britain that was used to transport salt from Poole Harbour in the later period, or the Mayen Ware (made with a potter's wheel) used for a range of storage functions. The Rhine also, of course, played a major role in the shipment of building materials, such as the trachyte quarried in Königswinter that was used in the construction of the legionary fortress and other buildings across the lower Rhine region. Ceramic industries emerged to supply wares both up and downstream of the Rhine, and bars of lead mined in the Eifel were exported via the Rhine as far afield as Sardinia. Such efforts were reliant on the effort of intermediary traders, negotiores, of whom one is attested operating between the mouth of the Rhine and Cologne via a votive inscription (CIL XIII 8793). Another trade known to have been based in Britain, and in which negotiatores, are known to have specifically specialised, was the wholesale trade of salt, an important export from Britain and the North Sea region. (Rothenhöfer 2014) 

Such trade opportunities were also driven by state demand. As mentioned elsewhere, the legionary fortress at Bonn was one of the largest on the lower Rhine, and it has for this reason been interpreted as a major supply hub for the entire Roman army in this region. This important role is reflected in the numerous harbour and landing sites which have been identified along the Rhine at the fortress, near to Königswinter, and in the region of the canabae legionis. 

The vicus south of the legionary fortress also saw a turnover of goods from across the Empire, especially the olive oil and wine which were ubiquitous throughout the Empire, and were packed in ceramic amphorae for bulk shipment. Interestingly, variation could be identified between the strip-houses, which consumed exclusively wine from Gaul, and the the house with high-quality wall decorations, which imported its wine from a range of locations further afield, including Italy and the Eastern Mediterranean: perhaps an indicator of superior economic connections or buying power. Curiously, the volume of exotic goods such as garum (a form of fish sauce which was a beloved condiment in the Roman period), oysters or mussels, was lower than in other settlements in the Roman Germanic provinces, which may have been indicative of a relativsmall scale purchase and distribution. (Höpken 2014; Helfert 2014) 

Roman products, such as luxury glass- and tableware, gold bullion, quernstones, currency, and high quality weaponry and armour were also in high demand among the social elites of the world East of the lower Rhine. Access to and distribution of these products played a role in the consolidation and stratification of societies in the lands beyond the Rhine, which acted as a crucial axis for access to these goods, and which may, therefore, have been a focal point for conflict and competition over such access. (Harland, forthcoming)