The History of the Kings of Britain

Written by Simon Williams

Written around 1136 by Geoffrey of Monmouth, The History of the Kings of Britain gave medieval England its first coherent national origin myth, tracing British kingship from the Trojan founder Brutus to the Saxon conquest and putting King Arthur at the centre of European imagination.

Key Facts

• Author: Geoffrey of Monmouth (Welsh cleric, c.1100 to 1155)
• Date Written: c.1136 CE
• Language: Latin
• Scope: From the founding of Britain by Brutus of Troy to the Saxon conquest (c.7th century AD)
• Key Characters: King Arthur, Merlin, Brutus of Troy, King Leir (Lear), Vortigern, Uther Pendragon
• Legacy: More than 200 surviving manuscripts; translated into French and English within decades
• Historical Status: Largely fictional; contemporary critics called Geoffrey a shameless fabricator

Geoffrey of Monmouth and the Invention of Britain's Glorious Past

Few books have exercised so profound an influence upon the imagination of the English-speaking world as Geoffrey of Monmouth's Historia Regum Britanniae. Written in elegant Latin around the year 1136, this single work contrived, almost single-handedly, to give medieval Britain a coherent and heroic national story: one that stretched back through the centuries to the fall of Troy and forward to the golden age of King Arthur.

Geoffrey, a Welsh cleric of considerable learning who rose to become bishop of St Asaph, presented his chronicle as a sober translation from an ancient British book lent to him by Walter, archdeacon of Oxford. No such book has ever been found, and scholars are now unanimous that Geoffrey was practising a form of literary invention that was not uncommon in his day. Yet the audacity of the claim only heightened the work's authority in an age that craved written proof of ancient lineage.

What Geoffrey delivered was nothing less than a continuous narrative of British kings from the arrival of Brutus, great-grandson of Aeneas, to the final triumph of the Saxons in the seventh century. In doing so he filled a yawning gap. The Normans who ruled England after 1066 possessed no equivalent to the grand origin myths claimed by the French or the Germans. Geoffrey supplied one, and in the process created a past so compelling that it was accepted as history for centuries.

The Early Kings and the Foundation of Britain

The chronicle opens with the exile of Brutus from Italy after he has unwittingly slain his father. Guided by the goddess Diana in a dream, he sails to a distant island inhabited by giants. There he founds New Troy (later London) and establishes a dynasty of British monarchs. We meet Dunvallo Molmutius, the lawgiver whose statutes were said still to be observed in Geoffrey's time; Bladud, the founder of Bath and a dabbler in necromancy; and above all Leir, whose story of division among three daughters would one day furnish Shakespeare with the tragedy of King Lear.

These early reigns are frankly fabulous, yet they serve a serious purpose: to demonstrate an ancient sovereignty and a continuous line of legitimate rule long before the Saxons set foot on British soil.

The Age of Arthur and the Wizard Merlin

It is with the arrival of Merlin and Arthur that the Historia reaches its dramatic climax. Merlin, born of a mortal woman and an incubus, yet choosing the path of righteousness, emerges first as a prophetic child who explains the meaning of the red and white dragons discovered beneath Vortigern's tower: the red representing the Britons, the white the Saxons, with ultimate victory promised to the native line.

Merlin then engineers the conception of Arthur by disguising Uther Pendragon so that he may lie with Igerna at Tintagel. Arthur himself is portrayed as a conqueror of continental Europe, a founder of the Round Table (though Geoffrey mentions it only in passing), and a king whose court at Caerleon dazzles with chivalric splendour. His final battle at Camlann against his treacherous nephew Mordred marks the end of Britain's imperial moment.

The Saxon Conquest and the Twilight of British Rule

The later books record the steady advance of the Saxons under Hengist and Horsa, the heroic but doomed resistance of Ambrosius Aurelianus and Uther, and the ultimate collapse of British power. Geoffrey does not disguise the tragedy: the golden age is over, the island's ancient glory eclipsed. Yet the prophecy of eventual British restoration lingers, a promise that would comfort generations of Welsh patriots and later Tudor propagandists.

The Astonishing Legacy

For all its inventions, the Historia Regum Britanniae was an immediate sensation. Manuscripts multiplied; French and English translations appeared within decades. Geoffrey's Arthur became the Arthur of romance; his Merlin the archetypal wizard of European literature. Shakespeare borrowed Leir; the Tudors claimed descent from Brutus to legitimise their rule; Malory drew upon the work to shape the Morte d'Arthur.

Critics, from William of Malmesbury in Geoffrey's own lifetime to Polydore Vergil in the sixteenth century, exposed the fictions. Yet the book was never wholly discredited. Its power lay not in accuracy but in vision: it gave Britain a usable past, a story of ancient greatness that could inspire pride and identity at a time when such things were urgently needed.

In the end, Geoffrey of Monmouth did not merely record history; he created a myth so potent that it has outlived every attempt to disprove it. The Historia Regum Britanniae remains one of the supreme acts of literary imagination in the medieval world: a work that, for better or worse, helped to make the British understand themselves as heirs to an heroic antiquity.

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This article is part of the Myths and Legends series on Histories and Castles.

Deepen Your Understanding

History rarely happens in isolation. The people, texts, and ideas on this page are part of a much bigger story. The articles below explore the threads that connect to what you have just read.

→ Historia Regum Britanniae: The source text, its reception across medieval Europe, and why it matters for understanding British history

→ Geoffrey of Monmouth: A Historical and Literary Figure: The man behind the chronicle, his life, education, and methods

→ Welsh Mythology and King Arthur: The Celtic Origins: The Welsh Arthur who preceded Geoffrey's literary invention by centuries

→ Welsh Mythology: The Complete Beginner's Guide: The wider mythological world that Geoffrey drew from and transformed

→ King Arthur: From Geoffrey's chronicle to medieval Europe's most popular legend

People Also Ask

Is the History of the Kings of Britain a true historical record?

In the modern sense, no. While Geoffrey claimed to be translating "a very ancient book in the British tongue," most historians believe he synthesised Welsh folklore, Latin chronicles, and his own considerable imagination. Even in his own time, contemporary historians like William of Newburgh criticised him for lying shamelessly. The work is best understood as legendary pseudo-history: imaginative and politically purposeful, but not factual.

How did Geoffrey of Monmouth create the legend of King Arthur?

Before Geoffrey, Arthur appeared only in fragmented Welsh poems and brief Latin entries. Geoffrey transformed him into a pan-European conqueror. He introduced key elements like the wizard Merlin, the sword Caliburn (later Excalibur), and the betrayal by Mordred, providing the blueprint for all later Arthurian romances. Without the Historia, the Arthurian tradition as we know it does not exist.

Who was Brutus of Troy?

According to Geoffrey, Brutus was the great-grandson of Aeneas of Troy. After accidentally killing his father, he was exiled and eventually led a group of Trojans to a "Great Island" then called Albion. He defeated the resident giants and renamed the land "Britain" after himself, establishing London as "New Troy." The story was entirely Geoffrey's invention, modelled on the Roman origin myth of Aeneas founding Rome.

What are the Prophecies of Merlin?

A central section of the book contains a series of obscure, animal-themed prophecies delivered by Merlin to King Vortigern. These were incredibly popular in the Middle Ages, as they were often reinterpreted to fit the political needs of various kings, including the Normans and later the Tudors. Geoffrey later expanded them into a separate work, the Prophetiae Merlini, which circulated independently.

Why was this book so important for the medieval English monarchy?

The Norman kings of England used Geoffrey's work to provide themselves with a prestigious ancestry that rivalled the French. By claiming the heritage of the ancient British kings and Arthur, they could justify their rule over the entire island and present themselves as the legitimate heirs to a glorious, ancient empire. Edward I in particular invoked Arthurian precedent to justify his conquest of Wales and his claims over Scotland.

What happened to the ancient British line of kings?

Geoffrey's narrative ends with the death of Cadwallader in the 7th century. He describes the British (Welsh) losing control of the island to the Saxons due to civil war and divine punishment, but leaves a glimmer of hope with the prophecy that the British would one day regain their sovereignty. This ending gave comfort to Welsh identity across the medieval centuries and was later seized on by Tudor propagandists claiming Welsh descent.

Primary Sources and Further Reading

• Geoffrey of Monmouth (c.1136) — Historia Regum Britanniae. Modern translation: Lewis Thorpe, The History of the Kings of Britain, Penguin Classics, 1966. The standard accessible English edition.
• Wright, Neil (ed.) (1985) — The Historia Regum Britanniae of Geoffrey of Monmouth, D.S. Brewer. Scholarly Latin text with critical apparatus.
• Tatlock, J.S.P. (1950) — The Legendary History of Britain, University of California Press. The foundational academic study of Geoffrey's sources and methods.
• Gillingham, John (1990) — "The Context and Purposes of Geoffrey of Monmouth's History of the Kings of Britain." In Anglo-Norman Studies 13, Boydell Press. Examines the political motivations behind the work.
• Roberts, Brynley F. (1984) — "Geoffrey of Monmouth, Historia Regum Britanniae and Brut y Brenhinedd." In Arthur of the Welsh, University of Wales Press. Examines the Welsh context and sources Geoffrey drew upon.

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