Trinovantum is the name in medieval British legend that was given to

London London is the capital and List of urban areas in the United Kingdom, largest city of England and the United Kingdom, with a population of just under 9 million. It stands on the River Thames in south-east England at the head of a estuary dow ...

, according to

Geoffrey of Monmouth Geoffrey of Monmouth ( la, Galfridus Monemutensis, Galfridus Arturus, cy, Gruffudd ap Arthur, Sieffre o Fynwy; 1095 – 1155) was a British cleric from Monmouth, Wales and one of the major figures in the development of British historiography ...

's ''

Historia Regum Britanniae ''Historia regum Britanniae'' (''The History of the Kings of Britain''), originally called ''De gestis Britonum'' (''On the Deeds of the Britons''), is a pseudohistorical account of British history, written around 1136 by Geoffrey of Monmouth. ...

'', when it was founded by the exiled

Trojan Trojan or Trojans may refer to: * Of or from the ancient city of Troy * Trojan language, the language of the historical Trojans Arts and entertainment Music * ''Les Troyens'' ('The Trojans'), an opera by Berlioz, premiered part 1863, part 189 ...

Brutus, who called it ''Troia Nova'' ("New Troy"), which was gradually corrupted to ''Trinovantum''. The legend says that it was later rebuilt by King Lud, who named it ''Caer Lud'' ("Lud's Fort") after himself and that the name became corrupted to ''Kaer Llundain'' and finally London. The legend is part of the

Matter of Britain The Matter of Britain is the body of medieval literature and legendary material associated with Great Britain and Brittany and the legendary kings and heroes associated with it, particularly King Arthur. It was one of the three great Weste ...

. The name ''Trinovantum'' derives from the

Iron Age The Iron Age is the final epoch of the three-age division of the prehistory and protohistory of humanity. It was preceded by the Stone Age ( Paleolithic, Mesolithic, Neolithic) and the Bronze Age ( Chalcolithic). The concept has been mostly ...

tribe of the Trinovantes, who lived in

Essex Essex () is a Ceremonial counties of England, county in the East of England. One of the home counties, it borders Suffolk and Cambridgeshire to the north, the North Sea to the east, Hertfordshire to the west, Kent across the estuary of the Riv ...

Suffolk Suffolk () is a ceremonial county of England in East Anglia. It borders Norfolk to the north, Cambridgeshire to the west and Essex to the south; the North Sea lies to the east. The county town is Ipswich; other important towns include ...

and part of

Greater London Greater may refer to: *Greatness Greatness is a concept of a state of superiority affecting a person or object in a particular place or area. Greatness can also be attributed to individuals who possess a natural ability to be better than al ...

and are mentioned by

Julius Caesar Gaius Julius Caesar (; ; 12 July 100 BC – 15 March 44 BC), was a Roman general and statesman. A member of the First Triumvirate, Caesar led the Roman armies in the Gallic Wars before defeating his political rival Pompey in a civil war, an ...

in his account of his expeditions to Britain in 55 and 54 BC. In a later account of those expeditions by

Orosius Paulus Orosius (; born 375/385 – 420 AD), less often Paul Orosius in English, was a Roman priest, historian and theologian, and a student of Augustine of Hippo. It is possible that he was born in ''Bracara Augusta'' (now Braga, Portugal), t ...

, they are referred to as ''civitas Trinovantum'', "the nation of the Trinovantes", with ''Trinovantum'' in this case being in the

genitive In grammar, the genitive case ( abbreviated ) is the grammatical case that marks a word, usually a noun, as modifying another word, also usually a noun—thus indicating an attributive relationship of one noun to the other noun. A genitive can a ...

plural The plural (sometimes list of glossing abbreviations, abbreviated pl., pl, or ), in many languages, is one of the values of the grammatical number, grammatical category of number. The plural of a noun typically denotes a quantity greater than the ...

. However, as ''civitas'' can also mean "city" and

Latin Latin (, or , ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through ...

neuter

noun A noun () is a word that generally functions as the name of a specific object or set of objects, such as living creatures, places, actions, qualities, states of existence, or ideas.Example nouns for: * Living creatures (including people, alive, ...

s often end in ''-um'' in the

nominative In grammar, the nominative case ( abbreviated ), subjective case, straight case or upright case is one of the grammatical cases of a noun or other part of speech, which generally marks the subject of a verb or (in Latin and formal variants of Eng ...

singular Singular may refer to: * Singular, the grammatical number that denotes a unit quantity, as opposed to the plural and other forms * Singular homology * SINGULAR, an open source Computer Algebra System (CAS) * Singular or sounder, a group of boar ...

, this phrase was misinterpreted by Geoffrey or his sources as "the city Trinovantum". In

Roman Roman or Romans most often refers to: * Rome, the capital city of Italy * Ancient Rome, Roman civilization from 8th century BC to 5th century AD *Roman people, the people of ancient Rome *''Epistle to the Romans'', shortened to ''Romans'', a lett ...

times, the city was known by the name

Londinium Londinium, also known as Roman London, was the capital of Roman Britain during most of the period of Roman rule. It was originally a settlement established on the current site of the City of London around AD 47–50. It sat at a key cros ...

, which appears to be cognate with ''Llundain'' and ''London''.

References

, ''

'' 1.17 *

, ''

Commentarii de Bello Gallico ''Commentarii de Bello Gallico'' (; en, Commentaries on the Gallic War, italic=yes), also ''Bellum Gallicum'' ( en, Gallic War, italic=yes), is Julius Caesar's firsthand account of the Gallic Wars, written as a third-person narrative. In it C ...

'' 5.20 *

, ''Seven Books of History Against the Pagans'
6.9
(Latin only) * {{Geoffrey of Monmouth History of London Geoffrey of Monmouth Traditional history of Julius Caesar's invasions of Britain