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12 February 2023

Mermaids, sirens and Alexander the Great

What's the difference between a mermaid and a siren? This isn't a trick question, but a conundrum that can occur when describing certain mythical creatures. Sirens are usually deadly creatures associated with enchanting melodies, whereas mermaids or merpeople are not threatening on the whole. Ariel, in the Disney animated film, The Little Mermaid (1989), based on the classic fairy-tale by Hans Christian Andersen, is not a harmful creature, but a young mermaid who wishes to become human and join our world above water.

Sirens, on the other hand, have different intentions. One of the oldest legends of sirens comes from ancient Greek mythology. In Book XII of Homer’s Odyssey, Circe warned Odysseus of the sirens he would encounter on his sea journey back to Ithaca. Odysseus followed Circe's advice and managed to resist the sirens' charms by plugging his sailors’ ears with beeswax. But Odysseus still wished to hear the sirens’ beautiful melody, and so he tied himself to the ship's mast to stop himself being lured by the sirens and turning off course into their shallow, rocky waters.

Two sirens attacking the sleeping crew of a ship. One siren is half-human, half-fish whilst the other siren is half-human, half-bird.

Two sirens attacking the sleeping crew of the ship, in the Queen Mary Psalter (England, 1310–1320): Royal MS 2 B VII, f. 97r

Sirens and mermaids also appear in legends about Alexander the Great. The fantastical elements of Alexander’s life stemmed from the tradition of the Greek Alexander Romance attributed to Pseudo-Callisthenes, translated and re-worked into many different languages during the Middle Ages. According to these popular legends, during his conquest Alexander and his soldiers came across a river full of reeds, where they discovered beautiful women with long hair down to their ankles. Unfortunately, the Macedonian conqueror soon discovered that these women were not as friendly as they first seemed, since they dragged some of his soldiers underwater, embracing them until they drowned, as illustrated in this French version of the Alexander Romance.

Alexander encountering naked women living in water. Depicted amongst the reeds is a woman pulling a man on top of her in an embrace.

Alexander encountering women living in the water (Southern Netherlands, c. 1290–1300): Harley MS 4979, f. 68r

A similar episode appears in our Alexander exhibition in a manuscript on loan from the National Library of Wales, preserving a version of the Historia de preliis in which Alexander’s soldiers managed to capture two sirens above water.

Alexander’s soldiers capture naked women with long hair by the river.

Alexander’s men encountering the sirens (England, 15th century) Aberystwyth, Llyfrgell Genedlaethol Cymru, Peniarth MS 481D, f. 90r

In some versions of the legends, Alexander and his soldiers also encountered a population of merpeople, naked humans who lived permanently in the sea, but were not violent or harmful to Alexander and his soldiers.

Three naked people stand in a river among reeds. Alexander and his soldiers observe from their riverbanks on horseback.

Miniature of Alexander encountering men and women living in the water (Rouen, c. 1445): Royal MS 15 E VI, f. 20r

The similar appearances and habitats of sirens and merpeople can make it tricky for adventurers to discern whether water-living humans are friend or foe. At one point during his ascent of Mount Purgatory, Dante Alighieri’s protagonist of the Divina Commedia is lured by a siren in a dream; it does not have a hybrid body, but appears as a beautiful woman, fully human, and singing. The poet describes how the woman’s decaying features turn beautiful as the pilgrim gazes upon her, and she starts to sing her melody. Fortunately, Dante is saved from the siren’s charm by Beatrice, who rips the siren’s clothes to reveal a horrible stench from her body, breaking her captivating spell.

Dante asleep, with the naked siren standing next to him. Dante appears again standing to the right of the siren and next to Beatrice. An angel dressed in green flies above them.

Dante’s encounter with the two Slothful and the Siren (Tuscany, c. 1444–1450): Yates Thompson MS 36, f. 98v

As we have seen, sirens have encompassed various forms. Classical tradition depicts them as part-woman and part-bird. During the Middle Ages, they also start to adopt a fish-like hybridity due to their association with water, or sometimes they have no obvious animal qualities like the sirens of the Alexander legends and the Commedia.

In bestiaries, sirens often appear accompanied by an illustration portraying their deceptive behaviour. In the example below, a siren is depicted alongside another hybrid creature, namely a centaur. In this illustration, one of the sailors plugs his ear in a similar manner to the sailors in the Odyssey, to block out the sound of the siren’s charm. Sadly, it's too late for his shipmate, who is already being pulled by his hair into the sea, entranced by the siren's beauty and her melody.

A siren, depicted as a woman with a fish tail, pulls a sailor from a boat. Another sailor stops his ears to avoid hearing the siren's song. A centaur holds a bow on the lower right.

Miniature of a siren pulling a sailor from a boat, next to a centaur (Northern France, 2nd or 3rd quarter of the 13th century): Sloane MS 278, f. 47r

Mermaids and sirens also frequently appear in the margins of Psalters as symbols of temptation. In the Luttrell Psalter a siren holds a mirror and a comb, perhaps as a warning against the lure of vanity and luxury.

Bas-de-page scene of a mermaid with a mirror and comb and a traveller being bitten by a dog.

Detail of a bas-de-page scene of a mermaid (England, 1325–1340): Add MS 42130, f. 70v

Our major exhibition Alexander the Great: The Making of a Myth is at the British Library until 19 February 2023. Tickets can be bought in advance or on the day, subject to availability, and you can explore more on our Alexander the Great website.

We are indebted to the Kusuma Trust, the Patricia G. and Jonathan S. England – British Library Innovation Fund and Ubisoft for their support towards the exhibition, as well as other trusts and private donors.


Giulia Gilmore

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