The Legend of Merlin, King Arthur’s Mysterious Wizard

Merlin is one of the most popular figures from the Arthurian legends, often reimagined in modern retellings. What do the original stories say about the wizard?

Published: Nov 26, 2025 written by Caleb Howells, BA Doctrines and Methodology of Education

Medieval depiction of Merlin and baby

 

The mysterious figure of the wizard Merlin is one of the most popular characters from the Arthurian legends. In most versions of the story, he is one of Arthur’s closest and most important allies, providing guidance in war and peace. Many of the most famous features of the Arthurian legends are tied to Merlin in some way, such as the Round Table and the Sword in the Stone. While different versions present Merlin in different ways, what is the basic story of this character in the Arthurian legends?

 

Merlin’s Birth and Parentage

merlin nuremberg chronicle
Merlin, Nuremberg Chronicle fol. 183r, 1493. Source: Wikimedia Commons

 

Given that Merlin is almost invariably shown to be a benevolent figure, helping Arthur fight against the forces of evil, his origin is quite surprising. The first record to provide Merlin with an origin story is Geoffrey of Monmouth in his Historia Regum Britanniae, written in c. 1137. He explains that a tyrant named Vortigern called for a boy without a father to be sacrificed at the site of a tower that he was attempting to build. Merlin is the boy who is brought forth, and in this passage, we learn of his origins.

 

According to Geoffrey’s account, Merlin was born from a spirit who visited his mother at night and slept with her. One of Vortigern’s men refers to this as an incubus, a specific type of male demon that violates sleeping women and produces demonic offspring. In other words, Merlin is portrayed as half-demon. Nevertheless, Merlin is consistently portrayed as a benevolent figure in Geoffrey’s account, something which he does not specifically explain.

 

merlin vortigern geoffrey monmouth
Young Merlin before King Vortigern, MS Cotton Claudius B VII, fol. 224. Source: British Library

 

Later versions of the story expand on this origin and explain why Merlin is not a force for evil. The major contribution to Merlin’s story was the poem Merlin, written in c. 1200 by Robert de Boron. While almost nothing of this poem survives, a prose version, possibly written by Robert himself in c. 1210, reveals what Robert wrote about this figure. This version is much the same as in Geoffrey’s account, but Robert specifies that Merlin was actually supposed to be the Antichrist.

 

However, Merlin’s evil destiny was prevented from coming to fruition by the actions of a character named Blaise. He is a priest who baptizes Merlin immediately after birth. This frees him from Satan’s power and explains why he is able to have a benevolent role in the legends.

 

Nevertheless, as a result of his supernatural origin, Merlin has miraculous abilities. He is able to shapeshift, as well as allow others to change their appearances. He also has supernatural knowledge of the past and present, while God bestows him with supernatural knowledge of the future.

 

Merlin’s Service to Ambrosius and Uther

conception arthur uther igerna
Image in the Prose Merlin by Robert de Boron depicting Uther with Igerna on the night of Gorlois’ death, c. 13th century. Source: Bibliothèque Nationale de France

 

The early part of Merlin’s career is fairly consistent between Geoffrey’s account and Robert’s Merlin. Merlin is presented as serving Ambrosius during his reign as king, overseeing his overthrow of Vortigern. During a break in Ambrosius’ wars against his enemies, Ambrosius desired to construct a large stone monument in honor of the British leaders who had been killed during the Saxon wars. To do so, Ambrosius decided to travel to Ireland to steal the “Giants’ Dance,” an existing monument. This proved too much for Ambrosius’ men, so Merlin used his magic to levitate the stones and fly them over to Britain, where they became Stonehenge.

 

Later, upon the death of Ambrosius, a dragon-shaped comet appeared in the sky. Merlin interpreted this as a sign representing his son Uther. Two rays that issued forth from the dragon’s mouth represented two of Uther’s offspring, Arthur and an unnamed daughter.

 

Most famously, Merlin used his magic to disguise Uther as Gorlois, duke of Cornwall. This allowed Uther to sneak into Igerna’s castle during a war with Gorlois and violate Igerna without her or any of Gorlois’ men suspecting anything.

 

Merlin and the Rise of King Arthur

arthur drawing sword stone
“He stood there holding the magic sword in his hand,” by Archibald Stevenson Forrest, 1906. Source: New York Public Library

 

The aforementioned union is what resulted in Arthur’s conception. In Geoffrey’s account, Arthur simply succeeds Uther without any strange occurrences. However, from Robert de Boron’s Merlin onwards, the story of Merlin involved him using his powers as a wizard to assist in the transition to Arthur’s rule. For unstated reasons, Merlin is said to have taken Arthur to Sir Erec to be raised in secret. Therefore, upon Uther’s death, when Arthur was a teenager, there was no clear successor.

 

Consequently, Merlin manufactured the challenge of the Sword in the Stone. He made this magical sword appear in a churchyard, stuck through an anvil and into a stone. On the side, it was written that only the rightful king could draw it out. Eventually, the young Arthur happens to take it, not even realizing its significance.

 

After repeating this action at all the important Christian festivals of the year, the people finally accept Arthur as their new king. In this way, Merlin assured Uther’s succession through Arthur.

 

Merlin’s Key Contributions to the Arthurian Legends

king arthur round table
King Arthur and his knights at the Round Table, in Prose Lancelot in manuscript BNF 112, by Evrard d’Espinques, 1470. Source: Bibliothèque Nationale de France

 

Merlin contributed greatly to various famous features of the Arthurian legends. According to Robert de Boron’s account, it was Merlin who constructed the Round Table, which he did in the reign of Uther Pendragon. Interestingly, this contradicts the earliest mention of the Round Table from Wace in c. 1155. Wace presented Arthur as having the Round Table constructed. Presumably, Robert de Boron changed this to provide Merlin with even greater importance.

 

Robert de Boron’s account ends with the accession of Arthur. However, later versions of the Arthurian legends, such as the Vulgate and Post-Vulgate Cycle, provide further details of his legendary career. In the Post-Vulgate Cycle, the distinction between the Sword in the Stone and Excalibur is first introduced (in earlier versions, they are the same sword). Merlin is responsible for Arthur’s acquisition of this second sword, just as he was for his first. He is described as taking him to a lake, where the Lady of the Lake famously sticks her hand out of the water and provides Arthur with Excalibur.

 

Merlin’s Loves: Vivian and Morgan le Fey

morgan le fay studied magic
“She was known to have studied magic while she was being brought up in the nunnery,” by William Henry Margetson, 1914. Source: University of Rochester

 

Merlin has another famous association with the Lady of the Lake, whose name was Nimue or Viviane (depending on the version). First, however, comes Merlin’s connection with Morgan le Fay. She was Arthur’s sister and one of the ladies-in-waiting of Guinevere, Arthur’s queen. After Guinevere discovers an affair between Morgan and Guiomar and demands that it stop, Morgan withdraws from Camelot in a rage. Thereafter, she goes to Merlin to be taught the magical arts so that she will be able to gain revenge against Guinevere. Since Morgan then goes on to become Arthur’s main enemy throughout his reign, Merlin’s own folly is profoundly evident here.

 

Merlin falls in love with Morgan, but his feelings are ultimately not returned. Morgan insists on rejecting Merlin despite his insistence, even threatening to harm him if he does not leave her alone. Nevertheless, she frequently calls on him for help, and he is always there to assist her. In fact, there is one insistence in which Merlin lies to Arthur to protect Morgan, which appears to be the only instance of Merlin doing such a thing to Arthur.

 

witches tree viviane merlin
The Lady of the Lake (Viviane) with Merlin in Witches’ Tree, by Edward Burne-Jones, 1882. Source: Wikimedia Commons

 

After this, Merlin falls in love with Viviane. His connection with this character varies considerably in the different tellings of the Arthurian legend. Nevertheless, there is wide agreement that Viviane was the object of Merlin’s love. Like Morgan, Viviane is portrayed as using Merlin to learn everything that she could about magic. After doing this, like Morgan, she rejects Merlin. Unlike Morgan, who apparently did sleep with Merlin in at least some versions of the legend, Viviane utterly refuses to have intercourse with him.

 

After using him to become a powerful sorceress, Viviane traps Merlin in an eternal prison. The exact nature of this prison varies depending on the version. In some versions, it is within a tree. In others, it is a cave. Others present it as a large, invisible tower from which there is no escape. In any case, Merlin is usually presented as offering little resistance, and after this, he is never seen again.

 

Who Is the Wizard Merlin?

merlin face carving tintagel
A modern carving of Merlin’s face at Tintagel, Cornwall, England. Source: photo by Caleb Howells

 

In summary, Merlin plays a vital role in most versions of the Arthurian legends. He was born from the union of a demonic incubus and a human mother, intended to be the Antichrist. Being baptized at birth, he was freed from this evil destiny and became benevolent. He is always portrayed as assisting the kings whom he served, such as Ambrosius, Uther, and Arthur. Using his magic, Merlin brought the “Giants’ Dance” over from Ireland for Ambrosius. He enabled Uther to disguise himself as Gorlois to take Igerna. Merlin assured Athur’s ascendancy to the throne by manufacturing the challenge of the Sword in the Stone, along with assisting him throughout his reign.

 

emil johann lauffer merlin king arthur
Merlin presenting the future king Arthur, by Emil Johann Lauffer, before 1909. Source: Sotheby’s

 

Merlin’s downfall was ultimately his passion for Morgan and, later, Viviane. Both of them were students of Merlin who learned everything they could from him, becoming powerful sorceresses before then rejecting him. In the case of Viviane, this resulted in Merlin becoming trapped in an eternal prison.

photo of Caleb Howells
Caleb HowellsBA Doctrines and Methodology of Education

Caleb is a published history author with a strong interest in ancient Britain and the Mediterranean world. He holds a BA in the Doctrines and Methodology of Education from USILACS. He is the author of "King Arthur: The Man Who Conquered Europe" and "The Trojan Kings of Britain: Myth or History?". Caleb enjoys learning about history in general, but he especially loves investigating myths and legends and seeing how they might be explained by historical events and individuals.