Rare 2,100-year-old gold coin bears name of obscure ruler from pre-Roman Britain

A gold coin minted by a little-known ruler in ancient Britain — an Iron Age man who said he was as "mighty" as a god — has been found by a metal detectorist and auctioned off in England.

The rare coin was discovered in March 2023 in Hampshire county and was auctioned Sept. 28 for 20,400 British pounds ($24,720), Spink auction house said in a series of statements.

A Latin alphabetic inscription on the coin bears the name "Esunertos," which can be translated as "mighty as the god Esos," (also spelled Esus) the statements said. The name itself is Gaulish, a language commonly spoken in the region at the time, John Sills, an archaeologist at the University of Oxford's Institute of Archaeology who examined the coin before it was auctioned, told Live Science in an email.

The coin dates to sometime between 50 B.C. and 30 B.C., a time after Julius Caesar invaded Britain twice around 55 B.C. to 54 B.C., the statement said. Caesar's invasions failed to establish permanent Roman control over Britain. It wasn't until after another Roman invasion, launched in A.D. 43 by Emperor Claudius, that the Roman Empire managed to gain long-term control over part of the island.

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This coin is one of only three on record that bear the name Esunertos, Sills said. All three were found in the same region, and it's possible that the territory controlled by Esunertos included part of what is now western Hampshire, Sills noted.

In the time after Caesar's invasions, the political situation in Britain may have been in flux, said Ian Leins, a curator of collections and interiors at English Heritage, a charity that manages the U.K.'s historic monuments. Rome had conquered Gaul by 50 B.C., and the threat of another invasion attempt in Britain loomed.

"Rome was meddling in the affairs of Britain and the Britons themselves were suddenly faced with a range of new opportunities and threats that resulted from the changing political landscape across the channel," Leins, who was not involved with the coin's analysis, told Live Science in an email.

"Within a rapidly changing political landscape, I suspect that new political leaders emerged; sometimes flourishing, sometimes disappearing as quickly as they had appeared," Leins said. "If an individual amassed enough power and wealth to extend his/her influence, the striking and issuing of coins was one mechanism by which they could further expand their influence."

Esunertos would have been one of these leaders and thus could mint his own coins, although we'll never know whether he actually called himself a "king," Leins said.

"His position was probably based on contacts, ancestry, land and/or control of resources," Leins said. "The rest is pure speculation… Was he a popular, charismatic, elected leader? Was his authority based on fear or brutality? We will almost certainly never know the answer to these questions!"