For more than 600 years, the chainmail worn by Roman soldiers was essential gear across the entire empire, no matter where a soldier was stationed. The further the frontier stretched from supply sources, however, the more precious metal became. In extreme circumstances, soldiers were required to conserve and begin recycling their chainmail.

The German frontier, which extended from the Danube to the mouth of the Rhine, was one such extremity. There, limited local capacity to supply metal to Roman soldiers created a need to recycle and reuse mail armor, which likely supported a cottage industry. This is one conclusion of Czech and German researchers whose findings were published in Antiquity on December 10.

One of the largest chainmail hoards was found in Bonn in 2012. Photo: courtesy J. Vogel.

The argument’s central piece of evidence is a heavily corroded 30-pound hoard of chainmail that was found in a shallow pit in 2012 outside of Bonna, a Roman legionary fortress in what is today Bonn, Germany. The hoard, which is housed at LVR Landes Museum in Bonn, has been labelled one of the largest and most important finds of mail armor from across the Roman world.

Small fragments from chainmail hoard in Bonn. Photo: courtesy J. Vogel.

After taking x-ray and CT scans, the researchers wrote that “based on the observed differences in ring size, we conclude that the hoard comprises four different mail coats. Differences in the diameters of the solid rings are the most important indicator.” Two chainmail armors were almost complete and only sections of the other two remained.

It was dated to sometime between the 2nd century C.E. and 3rd century C.E. based on the short-sleeve design, one “resembling a modern T-shirt” that replaced the sleeveless shirt with two shoulder guards. Another factor was the size of the rings—extra small rings were not used after the 2nd century C.E.

Left: detail of Great Ludovisi sarcophagus in Rome with short-sleeved chainmail. Right: digital reconstruction of chainmail coat from Vimose in modern-day Denmark. Photo: M.A. Wijnhoven.

The conclusion is that these soldiers on the northern Roman frontier would place armor that was no longer serviceable into piles that would be used to patch up and repair other chainmail garments. This process relied on labor from local workshops, the researchers wrote, with the hoard discovered at a settlement near a Roman military installation known as a vicus.

Such resourcefulness was not always the case. At sites occupied contemporaneously by Roman soldiers in the Lower Rhine, excavations have found waste dumps that include large quantities of metal, suggesting an ample supply. Upon first reaching an area, demand for metal was high, as it was also needed for construction materials, such as nails. Over time, this demand gradually decreased.

As for how the scrap metal ended up buried in a vicus, researchers believe the settlement was abandoned during the mid-3rd century and the mail was deemed too heavy to carry onward.