In 1868, when the Port of London Authority dredged the River Thames, an ancient Celtic bronze helmet was discovered.

The ceremonial helmet has repoussé decorations hammered into the reverse side of the metal; this design is in the style of La Tène art that was popular in Britain in the last few centuries BC.

The helmet, found near Waterloo Bridge, was made from two pieces of bronze riveted together to form the cap of the helmet. Two tapering horns tipped with terminal knobs are attached to each side of the top, and more rivets decorate the circumference as well as the spot where the horns join the cap.

As with most bronze objects, the patina was a weathered blue-green when it was discovered, but it has been brought back to life with a rich, polished bronze color. The piece may also have been decorated with pieces of red glass. Small holes dotted around the bottom edge indicate it may have had a lining when it was new.

Including the Waterloo Helmet, just three Iron Age helmets have ever been found in England. The Waterloo is the only horned helmet from that period ever found in Europe. Iron Age representations of soldiers wearing horned helmets helped archaeologists to date the artifact.

The helmet would not have been worn in battle, as the thin sheets of bronze would not have withstood combat; it was most likely intended for ceremonial occasions. Its small size indicates it may have been designed for a statue or effigy, since it would not fit most fully grown men. The helmet could have been thrown into the river as an offering of some type.

Gallic helmets are typically portrayed as having realistic bull horns rather than the straight horns found on the Waterloo helmet, which resemble a rabbit’s ears more than bull’s horns.

Representations on the Gundestrup Cauldron from the 1st century BC show an image of a figure holding a wheel and wearing a horned helmet of a different shape. The horns in the engraving are curved but, like those of the Waterloo Helmet, not sharply pointed. An Iron Age bas-relief at Brague, France also shows figures of men wearing horned helmets.

Currently, the Waterloo Helmet remains the only example of a horned helmet from the Iron Age; the other two helmets that have been found, the Meyrick Helmet and the Canterbury Helmet, have no horns. Modern artists portraying life in the Iron Age usually depict soldiers in horned helmets, but prolific author and former Cardiff University archaeology professor Miranda Aldhouse-Green remarks that it is “unfortunate that it has found such a firm place in many popular reconstructions of British warriors.”

Jeffrey Hildebrandt, a member of the Royal Oak Armoury and an experienced replicator of ancient helmets, re-created the Waterloo Helmet in 2014. The story of his failures and successes in creating the helmet is available here. After completion, the reproduced helmet sold for $2,750.

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The helmet is currently on display at the British Museum in London. One horn was broken and had to be replaced with a replica, but the piece is in remarkable condition, considering it lay at the bottom of the longest river in England for almost 2,000 years. The helmet traveled to the National Museum of Scotland in Edinburgh from March to September of 2016 and was featured in a special exhibition called “Celts: Art and Identity” at the British Museum in 2015-2016.