A mysterious Roman helmet that pre-dates the Roman invasion of Britain is to go on display at Fishbourne Roman Palace from next month (April 2022). Alongside the helmet, other pre-invasion artefacts – a sword scabbard fitting and an Iron Age crucible – will also be displayed.

In terms of what these objects mean for our understanding of our Roman past, visitors to the exhibition will find that their guess is as good as the experts’.

The helmet, known as the Oyster Helmet of Chichester, is one of just four Coolus helmets in the UK. It was produced during the first century AD, before the Romans began their conquest of Britain. It was acquired by the Sussex Archaeological Society in 1893, and though much of its journey has been lost to history, it is thought to have been found in the mud flats at Chichester Harbour, just a few miles from the Roman Palace at Fishbourne.

The scabbard fitting, which is made of copper alloy like the Chichester Helmet, sparks further debate. Though it is Roman, it was found in an Iron Age ditch. The crucible offers yet more evidence of Iron Age Britons having interacted with Romans pre-invasion. It contains cast brass, a Roman invention that requires zinc, a material which is not native to the UK.

Sarah Parker, Property Manager at Fishbourne Roman Palace, said: “It is surprising to find these items in a pre-Roman context, and we hope visitors to the exhibition enjoy playing detective! While we may not have enough archaeological evidence to suggest that the Roman invasion of Britain took place earlier than previously thought, there are a lot of questions to be answered.

“What we do have significant evidence of is a link between Iron Age communities in Sussex and the Romans – they could have been trading, training warriors, or even, though it’s unlikely, capturing Romans!

“So, how did the helmet get here, and who wore it? Well, it could have been collected by an antiquarian in Europe centuries after the Romans, and then lost overboard. It could be that a Roman soldier had kept his Coolus helmet even after newer helmet designs had replaced it. Maybe a local person had acquired and had decided to dress in Roman gear, we just don’t know!

“We know that the helmet was mass-produced, made cheaply for a lower status soldier, because it has very few decorations and was ‘spun’ on a lathe. It almost certainly wasn’t made in Rome. It could even be that this helmet was worn by an enslaved person, perhaps someone from Gaul, a region that spanned across modern Europe, who had been conscripted by the Roman army.

“Though the helmet had little in the way of decoration when it was worn, the passage of time has rectified this as, from its years underwater, today it boasts an oyster shell!”

The Oyster Helmet of Chichester will be on display at Fishbourne Roman Palace throughout the spring and summer seasons in 2022.

There is free parking and food available to purchase on site. Ticket prices start at £12 for an adult, £6 for a child and £11.50 for senior concessions. Family tickets are available at £20 for one adult and up to three children, or £35 for two adults and up to four children.

Members of the Sussex Archaeological Society can visit Fishbourne Roman Palace and the other Sussex Past heritage sites and museums, including Lewes Castle & Museum and Michelham Priory House & Gardens, free of charge. Membership starts at £40 for standard membership, £58 for joint membership and £70 for a family.

As the Society is a registered charity, it is possible to Gift Aid tickets.