Achilles’ Shield Decoded (summary)

The key to Homer’s Odyssey and the Trojan War

New perspectives

the Shield of Achilles by Sybren Vlasblom

In searching for other perspectives to interpret the Iliad and the Odyssey, I am taking my own approach. As a reader, but also as a traveller and sailor. With curiosity as the driving force, and uncertainty about the stories and the mysterious metaphors. Using current knowledge and technology. Letting go of fixed dogmas to create room for other ideas and theories. My focus lies on the Atlantic world. In the Greek world, no trace of Homer’s stories has been found. 


The new shield of Achilles: no art, but source of information

My inspiration and leads are derived from the new shield of Achilles, forged by the god Hephaestus. The shield has keys to unravel the secrets of the Iliad and Odyssey. The shield is made of 4 metals: gold, silver, copper and tin. It has 5 layers, of which several layers of bronze. On the shield are images of society in war and peace, of Oceanus and the dome of the sky with the sun, moon and 4 constellations.

There’s one more lead I have added: the dynamics of coasts. The sea has risen a few metres since the time of Odysseus and the coasts look different now than they did then.

It is my assumption that the Trojan War took place around 1400 BC. 


A shift in the Atlantic world ‘back then’

There was a highly developed Atlantic culture between 5000 and 1500 BC along the coasts and on all the islands of southern Spain and Portugal, Brittany and England, reaching as far as Scotland. Atlantic megaliths and other structures are older than those from the Greek golden age and Egyptian pyramids. The immense architectural and astronomical precision with which these megaliths were built is striking. Maritime shipping spread the knowledge and technology along the coasts. 

When gold, silver and copper were found in southern Spain, a crucial shift from stone to metals took place. Metals were also found elsewhere along the Atlantic coast. The finds attracted seamen and traders from the Mediterranean region from around 3000 BC. In southern Spain, a powerful centre developed where the metals were mined, brought in, processed and traded. When it turned out that copper with tin makes strong bronze, which could be used to forge stronger weapons, the trade demand shifted to tin: whoever has tin and can make bronze has the power. The rare tin became ‘worth its weight in gold’. Tin is rare in southern Spain but abundant in other Atlantic regions such as Cornwall, Galicia and Brittany. From 2200 BC Cornwall became the most powerful producer and supplier of tin to the trading centre and southern Spain became more dependent on the supply of tin from Cornwall (fig. 1). That led to tensions.

Fig. 1: The two centres of power in the Atlantic world: southern Spain and Cornwall 

Homer talks about increasing conflict between two centres of power, Ithaca and Troy. The tensions between Ithaca and Troy arose after the beautiful Achaean Helen, wife of king Menelaus, was abducted by the Trojan prince Paris during his visit. Negotiations between the kings of Ithaca and Troy did not lead to the return of Helen and the Trojan War broke out.


For me, a different reality arises in the Atlantic world. The cause of the Trojan war was not the abduction of Helen, but the struggle for power over tin.

The king of Cornwall is aware of his position of power and plans to deploy it against the rich traders in southern Spain. He sends his son to the kings of southern Spain. He comes with additional conditions that the king of Cornwall attaches to the supply of tin. The kings of southern Spain are afraid of losing their lucrative trade and do not agree to the demands. The balance of power is in danger of being upset and the conflict leads to war. Cornwall is attacked and the king’s castle is destroyed, the leaders killed. 

Both sides suffer enormous losses of kings and troops. On the home fronts, the populations become very weak and descend into chaos and poverty. Many inhabitants move away by sea and land, in search of better places. This is the end of an illustrious Atlantic era. It could be that they are the migrants who settled in Greece, as Plato and Herodotus thought. 

Perhaps they are the sea people who attacked Egypt with their ships in 1207 and 1177 BC and entered it by land.


My surmise is that Ithaca was the name Homer used for the centre of power in southern Spain, well known for the richness of gold, silver and copper. Homer describes Ithaca in the Odyssey as ‘an island/peninsula with a hill’, ‘between 2 seas’ and ‘with some islands nearby’. This corresponds to the peninsula with Huelva at the mouth of the Rio Odiel and Rio Tinto around 1500 BC (fig. 2). In this line of reasoning, Ithaca is the name for the area that later included Tartessos and now the city and province of Huelva.

Fig. 2: The bay with Ithaca on the peninsula, where present-day Huelva is located. 

Troy was the name Homer used for the centre of power in Cornwall. Troy is described as an elevated impregnable castle in the tin-rich area on or near the sea coast. There was a bay providing shelter from storms from the north, which was large enough for a fleet and daily battles. In this reasoning, Troy is the name for the rock that used to be called ‘Grey Rock in the forest’ and Iktin, and is now St Michael’s Mount. The rock used to be on land and is now in the sea due to a rise in sea level (fig. 3).

Fig. 3: Sea view of the high-lying castle of Troy, the present-day St Michael’s Mount 

Oceanus of ‘then’ is the North Atlantic of ‘now’

It has long been known that the circular Gulf Stream and the clockwise winds are the dominant unique characteristics of the North Atlantic Ocean. The current goes southwards from England to Spain to Cape Verde, and then westwards. In the Caribbean, the Gulf Stream goes to the northwest and bends north of the Bahamas eastwards to the Azores. 

Homer wrote that Oceanus surrounds the round shield of Achilles. This can also be seen as a representation of the circular flow in the ocean. The route of Odysseus is shown in fig. 4.

Odysseus’s route across the Atlantic Ocean

Fig. 4: Odysseus’s route across the Atlantic Ocean. 

Ocean navigation is determined, more accurately than by the sun, by 4 constellations on the Achilles shield. Using the SkyMap astronomy software, it is possible to study the night sky in 1400 BC. The Great Bear is always in the north. If there are two stars on the horizon perpendicular to each other, that is the right course. To the west, in winter, is the setting Betelgeuse (Orion) and directly above, Procyon (Canis minor) (fig. 5). In the summer, heading towards the home port in the east, there is the rising Saiph (Orion) and Aldebaran (Hyades) directly above it (fig. 6). The vertical lines of stars function just like 2 harbour lights perpendicular to each other indicating the safe course. Each harbour has its own combination of stars. This method of navigation is used by Polynesian sailors; it is a form of latitude sailing. Some stars mentioned in the Iliad and Odyssey act as a pointer for a skipper about the progression of the season. When these stars rise before the sun for the first time, a certain area must be left because of the threat of heavy storms. When the Pleiades rise earlier than the sun at the end of April, the ship must leave the Caribbean. Later in the season, something similar happens with Orion and Sirius. With this knowledge of the ocean and the night sky, it is possible to cross the ocean safely – there and back to the home port in 1 or 2 years. For more than 8 years, Odysseus stayed with the goddesses Circe and Calypso. Without a doubt, excellent places to spend the winter …

The western horizon with Procyon vertically above Betelgeuse in 1400 BC, the route from Boa Vista to Guadeloupe

Fig. 5: The western horizon with Procyon vertically above Betelgeuse in 1400 BC, the route from Boa Vista to Guadeloupe.

The eastern horizon with the vertical of Saiph (Orion) and Aldebaran (Hyades) between Norfolk, Azores (Ogygia) and Huelva (Ithaca). To the right the south east route between Azores and Lanzarote (Scheria) with the vertical of Alnilam (Orion) and the Pleiades

Fig. 6: The eastern horizon with the vertical of Saiph (Orion) and Aldebaran (Hyades) between Norfolk, Azores (Ogygia) and Huelva (Ithaca). To the right the south east route between Azores and Lanzarote (Scheria) with the vertical of Alnilam (Orion) and the Pleiades.

In Odysseus’ time, 1400 BC, the sea level was 3-5 metres lower than now

and coastal areas look significantly different now, compared to how they looked in the past. Two examples: 

Due to sea level rise, a broad strip of land on the coast of Mount’s Bay in Cornwall was swallowed up by the sea. The steep rock St. Michael’s Mount is now situated in the sea. But long ago the rock was on land in a forest. At the time of the Trojan war, the rock was on the coast or on a peninsula.


Large parts of the current sea area around the islands of the Bahamas are very shallow (0-8 metres water depth). As a result of the sea level rise of 3-5 metres over 3,400 years, large areas that were above sea level in the time of Odysseus have disappeared just under water. 


Metaphors and reality

Some metaphors in the Odyssey attract attention. The island of the king of the winds (in the Caribbean) is a ‘floating island, surrounded by an unbreakable wall of bronze’. That is an island, surrounded by a calm sea within a coral reef. Some islands in the Caribbean, especially Barbuda, meet this description. Elsewhere in the Atlantic Ocean, this situation occurs only around Barbados and the Bermuda Islands.

When Odysseus has to go from the goddess Circe to the house of Hades, he sails across a ‘river-stream’ and then arrives in Hades on the ‘extreme edge of the deep Oceanus’. This can be interpreted as a sailing trip from Aeaea, an island in the Bahamas, to the coast of Florida, across the fast-flowing Gulf Stream (so Odysseus was in Hades on the American coast!). On the return journey, the sun rises exactly in the east above Aeaea, the island of Circe.

Odysseus meets the goddess Calypso on the island of Ogygia. The god Hermes calls this island the ‘navel of the sea’, ‘in the middle of that immense salt lake without a city nearby where sacrifices are made to the gods’. My interpretation is that it could be an island in the Azores. After 7 years with Calypso he can go home, albeit with a detour. Calypso’s sailing instruction takes Odysseus across the Atlantic to Scheria, Lanzarote, where the Phaeacians live. A leading factor is the vertical line of stars with the rising Alnilam (Orion) and the Pleiades right above it (fig. 6). Nausicaa says that her island is ‘far from the people in the middle of the fiercely swaying sea’. Calypso’s sailing instruction is feasible in the Atlantic Ocean but not in the Mediterranean Sea. You would end up in the desert there. The Phaeacians bring Odysseus to Ithaca (Huelva). There he meets his son Tele­machus and finally embraces his wife Penelope. The journey home is complete.


The origin of the Iliad and the Odyssey

The new shield of Achilles, made by the god Hephaistus, was my source of inspiration. The strong round shield is made of bronze, an alloy of copper and tin. It is decorated with gold and silver and surrounded by Oceanus. Essential constellations are depicted. It was the struggle for power over tin that led to the Trojan war. The Iliad and Odyssey have a historic heart about the fall of a flourishing Atlantic culture and about the knowledge and technology to sail the ocean and find the home port again.

The Iliad and Odyssey are not merely works of fiction; they are examples of oral history. For centuries, migrated Atlantic peoples took their history and knowledge to their new homes, such as Greece. Homer placed the stories in a Greek setting with Greek gods and in his own era. Thanks to Homer, the stories are still alive.