The tablet says a man called Silvianus had lost a ring, and it asks Nodens to place a curse of ill health on Senicianus until he returned it to the temple.
An archaeologist who looked into the connection between the ring and the curse tablet asked Tolkien, who was an Anglo-Saxon professor at Oxford University, to work on the etymology of the name Nodens in 1929.
The writer also visited the temple several times, and some believe he would have been aware of the existence of the Roman ring before he started writing The Hobbit.
"The influences most often cited for Tolkien's creation of The One Ring usually take the form of literary or legendary rings," said Lynn Forest-Hill, education officer for the Tolkien Society.
"It is, then, particularly fascinating to see the physical evidence of the (ring), with its links to Tolkien through the inscription associating it with a curse," she said.
The gold ring is displayed at The Vyne, a historic mansion in southern England, starting Tuesday.
- AP