Trinovantes Celtic Tribe

The Trinovantes were an Iron Age Celtic tribe that held sway over the northern Thames Estuary, from the area around London to the east coast and northwards into lower Suffolk.  Like their neighbours in the south-east, they were probably a Belgic tribe from the North Sea or Baltics, part of the third wave of Celtic settlers in Britain.

The Realm of the Trinovantes according to Ptolemy

“Farther eastward [from the Catuvellauni] and near the Thames Estuary are the Trinovantes and the town Camulodunum 21*00 55°00.”

Geographia of Ptolemy (II.ii)

The Trinovantes tribe inhabited the modern county of Essex and much of southern Suffolk. The first Roman Colonia in Britain was established within the tribal territories at Colchester in 49AD. They were bordered to the north by the Iceni, to the south by the Cantiaci and to the west by the Catuvellauni. The tribal name Trinovantes possibly means ‘The Vigorous People’.

The Civitas Trinovantum The Principal Tribal Centre

Caesaromagus: The Roman civitas capital of the Trinovantes. The name of this town, meaning ‘The Field of Caesar’, may point to the town being founded on (or near) the site of a battle fought between the Romans and the Britons in 43AD.

The Tribal Πολις Assigned by Ptolemy

Colchester(Camulodunum): The only town mentioned by Ptolemy was the ancient tribal capital of the Trinovantes, which had been wrested from them during a war with the neighbouring Catuvellauni c.9AD. After the Roman invasion the town became the site of the first Roman Legionary Fortress in Britain and was later to become the first Roman colonia in the province. Both establishments were self-administrating and were allocated a large proportion of the original Trinovantian tribal territories.

Other Settlements and Places of Interest

  • Canonivm: (Rivenhall, Kelvedon, Essex) – Mentioned in the Antonine Itinerary and the Peutinger Table.
  • Combretovium: (Baylham House, nr. Coddenham, Suffolk) – A minor settlement at an important road junction.
  • Dvrolitvm : (Romford, Essex) – Mentioned in the Antonine Itinerary, but not supported by archaeological evidence.
  • Sitomagvs : (somewhere near Dunwich, Suffolk) – Mentioned in the Antonine Itinerary, and in the Peutinger Table as Sinomagus, has now been engulfed by the sea.
  • Villa Favstini? : (Scole, Norfolk) – Posting station and minor settlement on the road north between Colchester and Caistor-by-Norwich, possibly to be identified with the Villa Faustini of the Antonine Itinerary.
  • Long Melford: (Suffolk) – Minor settlement and posting station north-west of Colchester.
  • Stoke Ash: (Suffolk) – Posting station on the road north between Colchester and Caistor-by-Norwich.

Trinovantes and Caesar

It is possible that the Trinovantes were one of only two British tribes who sent the required tribute and hostages to Gaul where Caesar was wintering after his initial expedition to Britain in 55BC (vide Caesar B.G. iv.38).

… the Trinobantes, the strongest state, perhaps, in those parts … sent deputies to Caesar, promising to surrender to him and to do his commands, and beseeching him to protect Mandubracius¹ from outrage at the hands of Cassivellaunus, and to send him to their state as ruler and sovereign lord. …

  1. Mandubracius was the exiled king of the Trinobantes. His father (unnamed by Caesar) had been slain by Cassivellaunus, and the Trinovantian prince forced to flee to the continent and the protection of Caesar.

Shortly after the Atrebates tribe were taken into his protection, Caesar defeated the army of Cassivellaunus near Wheathamstead, soon afterwards receiving the submission of the last of the hostile British tribes. Seeing all was lost, their appointed leader Cassivellaunus himself surrendered, trusting to the famed clemency of Caesar.

Caesar, obviously learning from his previous mistake, this time waited until all of the British hostages had been delivered to him in Kent, before moving his forces back to the continent where they were to spend the winter of 54/53BC. Prior to stepping aboard his trireme, he issued the resigned British warlord a warning:

… He straitly charged Cassivellaunus to do no hurt to Mandubracius or the Trinobantes.

Caesar, De Bello Gallico v.22

Julius Caesar was destined never to return to Britain – indeed, no Roman general was to set foot on the island again for almost one hundred years – but the influence that he had on the future political development of the southern British tribes cannot be underestimated.

Dubnovellaunos Refuges with Augustus

There is a passage in the Res Gestae of the emperor Augustus which mentions the names of two reges Britannorum, or ‘Kings of the Britons’.

“The following kings sought refuge with me as suppliants: … of the Britons; Dumnovellaunos¹ and Tim[…]² …” (Augustus Res Gestae vi.32)

  1. Inscribed coinage recovered from the south-east of Britain, shows that there were two kings of this name: in Cantium, and in Essex.
  2. Both the Greek and Latin inscriptions are here defective; the name may be restored as Ti[ncom]m[ius], the Atrebatean monarch known to us through his coinage (vide hic).

It is thought that Dubnovellaunus travelled to Rome and paid tribute to Augustus before 7AD, and this is recorded in the Res Gestae. When the Roman general Varus lost three legions in the German Teutoberger forest in 9AD, it appears that Cunobelin of the Catuvellauni took the opportunity to attack and capture the Trinovantian capital. It is very likely that Dubnovellaunus would have travelled to Rome once more to plead his case before Augustus, but with the critical situation on the German borders the emperor was in no position to enforce discipline in Britain. The Varus disaster and the second visit by the Trinovantian king went unrecorded; the Res Gestae after all, listed Augustus’ triumphs, not his failures.

Tribe Active in the Rebellion of Boudicca 60/61AD

The trinovantes were later to have a significant role in the revolt associated with Queen Boudicca of their northern neighbours the Iceni. It is though likely that the primary reason for their joining the revolt was that they had not had their tribal lands returned to them after the defeat of Caratacus and the Catuvellauni.

… they [the Iceni, who occupied Norfolk, northern Suffolk and eastern Cambridgeshire.] flew to arms, and incited to rebellion the Trinobantes and others, who, not yet broken by servitude, had entered into a secret and treasonable compact to resume their independence. …

Cornelius Tacitus – The Annals, Book 14, Chapter 24

Who were the others? Probably a large contingent of the Catuvellauni, possibly joined by smaller forces from the Coritani and the Dobunni.

Further information on Boudicca‘s rebellion of 60/61AD may be found on the RBO WebPage dealing with the Iceni.

The Trinovantian Kings 


Imanuentius is named in some manuscripts of Julius Caesar’s De Bello Gallico as a king of the Trinovantes, the leading nation of south-eastern Britain at that time, who ruled before Caesar’s second expedition to the island in 54 BC. Variant spellings include Inianuvetitius, Inianuvetutus and Imannuetitius. In other manuscripts this king’s name is not given.

Imanuentius was killed by the warlord Cassivellaunus, and his son Mandubracius fled to the protection of Caesar in Gaul. Cassivellaunus then led the British defence against the Romans, but the Trinovantes betrayed the location of his fortress to Caesar, who proceeded to besiege him there. As part of the terms of Cassivellaunus’s surrender, Mandubracius was installed as king of the Trinovantes, and Cassivellaunus undertook not to make war against him.

Mandubratius … whose father, Imanuentius, had possessed the sovereignty in that state, and had been killed by Cassivellaunus

Caesar, De Bello Gallico v.20


Was regarded by Caesar as the most powerful of the British tribal monarchs in 54BC. Nothing further is known about him. The next identifiable ruler of the Trinovantes was Addedomaros who started his rule c.20-15BC, but whether he was the son or grandson of Mandubracius is not known; indeed, it is possible that Mandubracius was the last of his line, and that his throne was taken by, or given to the family of Addedomaros.


Was the next identifiable ruler of the Trinovantes after Mandubracius in Caesar’s time, though it is not known whether any others preceded him. Almost immediately upon his succession to the throne sometime between 25 to 15BC, he moved his centre of government from Braughing on the eastern headwaters of the river Lea to a new site on the east coast which he named ‘the fort of the war god Camulos’, or Camulodunum. It is possible that he either warred with or was client to Tasciovanus, for around 15-10BC the Catuvellaunian monarch produced a coin issue with the mint mark CAMV[lodunum]. He reigned for about a decade or so before being succeeded by his son Dubnovellaunus c.10-5BC. It is possible Mandubracius died intestate or leaving no heirs; the family of Addedomaros, possibly championed by his father, succeeded to the throne after a brief struggle between the remaining Trinovantian noble houses; the Catuvellaunian king Tasciovanus later claimed that he was the true heir to the throne (perhaps his mother was the daughter of Mandubracius) and went to war on that pretext; thanks primarily to the interest of Rome, Tasciovanus was forced to withdraw and Addedomaros resumed the throne.


Succeeded Addedomaros to the Trinovantian throne c.10-5BC and ruled for several years before being supplanted by Cunobelin of the Catuvellauni. Like his contemporary Tincommius of the Atrebates, he appeared as a suppliant to Augustus and paid tribute on the Capitol in Rome before 7AD. He should not be confused with Dubnovellaunus of the Cantiaci.

References for The Trinovantes

  • Peoples of Roman Britain : The Trinovantes by Rosalind Dunnett (Duckworth, 1975);
  • The Geography of Claudius Ptolemaeus, trans. by E.L. Stevenson (Dover, New York, 1991);
  • Atlas of Great Britain by the Ordnance Survey (Country Life, 1982);
  • Historical Map and Guide: Roman Britain by the OS (4th Ed., 1990);