This phantom island was once believed to lie in the Strait of Belle Isle

Somewhere in the Strait of Belle Isle dividing Newfoundland from Labrador lies an island perpetually shrouded in mist. Although its terrain is lush and its wilderness abundant with wildlife, no one lives there because any human being who sets foot on its shores is harassed day and night by evil spirits who jabber unintelligibly and conjure terrifying illusions.

This is the Isle of Demons, and it's one of the fabled phantom islands of the Atlantic land masses that appeared on European maps during the Age of Exploration only to be expunged when they couldn't be found again.

The Isle of Demons first appears on a 1508 world map by Dutch monk and artist Johannes Ruysch.

When Ruysch was in his 30s or early 40s, he sailed from the south of England to Newfoundland, possibly with John Cabot's 1497 expedition on behalf of the British Crown. A decade later, as one of few Europeans to have traveled so widely, he was asked to draft an updated map of the world to be published in a new edition of Ptolemy's Geography.

The chart he prepared, which incorporated information from the explorations of Cabot, Christopher Columbus, and Marco Polo, was only the second European map to include parts of North America. It shows Greenland and Newfoundland although both are depicted as peninsulas of Asia and, lying between them, a pair of islands where, according to the inscription, demons had attacked passing ships.

Almost 50 years later, Italian cartographer Giacomo Gastaldi included a more detailed representation of this "Isle of Demons" on his map of New France. Now clearly situated between Newfoundland and Labrador, Gastaldi's island is home to bat-winged devils and gryphon-like birds.

In the land of demons

Frenchman Andr Thevet like Ruysch, a monk-turned-explorer wrote of the Isle of Demons in his 1575 Universal Cosmography. He called it the biggest and most beautiful of the islands along the coast of Newfoundland, but noted that it was uninhabited due to the mischief caused by the devils who made their home there.

The island's otherworldly atmosphere could be felt even by sea. When sailors passed along this coast "it was as if they were buffeted by a great tempest and they heard in the air, about the tops and the masts of their vessels, human voices making a great din, but there was no form to their speech, only such a murmuring as you might hear in the middle of a public hall on a market day."

Thevet had an even more remarkable story to tell of the island, straight from the mouth of the woman who had experienced it.

In 1542, noblewoman Marguerite de La Rocque was bound for New France on the colonizing mission of her relative Jean-Franois de La Rocque de Roberval. But when Roberval discovered she was having an affair with another passenger, he abandoned the lovers and Marguerite's servant, who had stood guard during their trysts, on the Isle of Demons as punishment.

The trio built a small shelter and survived on foraged plants and the game they hunted using four guns Roberval had left behind for them. At first the demons, appearing in the guise of terrifying beasts, tried to tear down their hut, and in the dark of night they were surrounded by a cacophony of inhuman screeches.

As Thevet tells it, their piety and repentance eventually mollified the spirits but weren't enough to save them from nature's brutality. Eight months into the ordeal the man died and, nine months later, so did the servant and the baby Marguerite had birthed on the island.

For another full year, Marguerite survived alone until one day some fishing boats from lower Brittany passed and she was able to signal them by building a bonfire on the beach.

Thevet met Marguerite in Nontron, back in France, where she may have become a schoolmistress. Though her story sounds far-fetched, it has a few tantalizing details that suggest it was based on first-hand experience of North America, like the tidbit that in her time on the island she killed a bear as white as an egg.

Undiscovered country

The Isle of Demons slowly disappeared from maps over the course of the 17th century as the geography of the North Atlantic became better known to Europeans.

Based on its position between Newfoundland and Labrador, it's been variously identified as Belle Isle, Quirpon Island, Fischot Islandor even Caribou Island, off Labrador's east coast. Residents of Qubec's Harrington Island, in the Gulf of St. Lawrence, believe Roberval's castaways were marooned there and sheltered in a place now known as Marguerite's Cave.

If it was a real island, though, what would explain the supernatural phenomena people experienced there?

The cries that could be heard offshore might have been the calls of the hundreds of thousands of seabirds that breed on rocky outcrops along the Atlantic coastline. Renaissance sailors timed their arrivals in North America for May or June to avoid pack ice, exactly when Newfoundland and Labrador's shores were most likely to be shrouded in fog and the disembodied croaks of gannets or great auks would have drifted through the mist.

As for the demons that beset Marguerite, they could have been wild animals that were unfamiliar to her, like walruses or bald eagles, or simply the elements playing on her mind in that desolate landscape.

Still, there's something unsatisfying about those explanations. European sailors would have been well acquainted with North Atlantic seabirds, and Marguerite acknowledged that there were earthly animals like bears on the island, distinguishing them from the spirits that harassed her.

Perhaps we want to believe the world is marvellous and strange, to see magic at the edges of our maps. Or perhaps the Isle of Demons is still out there, hidden in the fog, just waiting to be rediscovered.

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