For more than 30 years, a remarkable collection of helmets believed to date from the Roman period has been recovered from the waters off Spain. New research has now overturned that belief, revealing that the artefacts are in fact medieval and provide rare information about arms movement, trade and military activity in the Mediterranean during the late Middle Ages.
The study, led by researchers at the University of Alicante (UA), re-examined 43 helmets discovered in 1990 at the underwater archaeological site of Piedras de la Barbada, near Benicarlo on the east coast of Spain. The findings, published in the journal Cambridge University Press ancient timesshow that the helmets were produced between the late 14th and early 15th centuries, completely overturning their long-standing Roman classification.
The research was led by Manuel Fralicciardi, a doctoral student jointly supervised by the University of Alicante and the University of Salerno.
The largest medieval helmet hoard in the western Mediterranean
This discovery happened by chance. Local fishermen pulled in their nets two large lumps of metal that had become fused together due to centuries of sea corrosion. Inside the concrete blocks was an extraordinary hoard of iron helmets.
Although archaeologists believe the original shipment may have contained even more pieces, the surviving collection of 43 helmets already represents the largest known hoard of medieval helmets found in the western Mediterranean.
According to Raimon Graals, a lecturer at the University of Alicante, co-director of Fraliciardi’s doctoral project, and co-author of the study, the significance of the discovery extends far beyond the artifacts themselves.
He said, “We are seeing direct evidence of a large-scale arms trade. This discovery reveals a network of exchange and communication that was far more complex than previously thought.”
The findings now point to the active movement of military equipment between the coast of the Valencia region and the major commercial centers of northern Italy, including Genoa, one of the most powerful trading centers of that era. Researchers say the size of the shipment indicates that the weapons were being transported through well-established commercial systems linking different parts of the Mediterranean.
New analysis reveals medieval origins
One of the most important advances of the study was the use of an analytical method developed at the University of Alicante. Although this technique has been used successfully in other archaeological investigations, it had never before been applied to medieval weapons of this type.
The approach combined with radiocarbon dating of fragments of cloth preserved inside several helmets allowed researchers to establish highly accurate ages for the artifacts.
Fralisciardi said identifying the helmet initially proved difficult.
“Initially, it was difficult to place them in a specific era because they had features that were reminiscent of both late Roman models and potentially medieval pieces inspired by classical traditions,” he said.
The results became even more surprising when the researchers discovered that the helmets did not match any previously recorded category.
Fraliciardi said, “When I started the research, it was incredible to see that practically no known parallels existed.”
While searching for comparisons, he found some similar helmet depictions in 14th-century English artwork, but no exact equivalents. Carbon-14 dating ultimately confirmed that the helmets were of a poorly documented design from a transitional period in military technology, with no direct descendants.
A lost shipment preserved beneath the sea floor
Researchers believe that all 43 helmets were originally part of the same cargo. The most likely explanation is that the shipment was being loaded or unloaded when an accident caused it to fall overboard.
The site is only six meters (20 ft) deep and is located next to an area that served as a pier.
Grells suggested that some of the cargo may have been buried under sand immediately after the accident, hampering recovery efforts at that time. As a result, the shipment remained hidden for centuries.
The helmets survived in exceptional condition due to a combination of sediment and mineral deposits that had formed around them underwater. In many cases, these solid materials sealed the interior lining, preserving pieces of fabric that would normally have decayed long ago.
Those textile fragments eventually became one of the most important sources of evidence in reconstructing the history of the collection and the era.
Piracy, war and demand for weapons
Researchers believe the shipment sank during a particularly volatile period in the history of the Mediterranean.
In the mid-14th century, Islamic piracy expanded along the Valencian coast, while increasing militarization created an increasing demand for protective equipment and weapons. In that environment, the helmets may have belonged to local militias, forces serving the Kingdom of Valencia, or armed groups responsible for defending the maritime border of the region.
Far from being Roman relics, the helmets now offer rare evidence of medieval trade, military logistics and the movement of arms in one of the world’s most important commercial regions.