Rabbits arrived in the country 1,000 years earlier than previously thought and could have even been kept as an exotic pet, carbon dating has revealed.
The 4cm segment of bone was discovered during excavations in 1964 at Fishbourne Roman Palace, but it remained in a box, unrecognised until 2017, when Historic England zooarchaeologist Dr Fay Worley realised the bone was from a rabbit.
The discovery suggests the animal could have been kept in confinement as an exotic pet, as the rabbit does not bear any butchery marks.
Rabbits are native to Spain and France and it had been thought they were a medieval introduction to Britain, but radiocarbon dating of the bone shows the rabbit was alive in 1AD.
Academics from the Universities of Exeter, Oxford and Leicester carried out the analyses.
Further research is continuing to determine where the animal came from and whether it is related to present-day rabbits.
Professor Naomi Sykes, from the University of Exeter, said: “This is a tremendously exciting discovery and this very early rabbit is already revealing new insights into the history of the Easter traditions we are all enjoying this week.
“The bone fragment was very small, meaning it was overlooked for decades, and modern research techniques mean we can learn about its date and genetic background as well."
Dr Worley said: “I was excited to find a rabbit bone from a Roman deposit, and thrilled when the radiocarbon date confirmed that it isn’t from a modern rabbit that had burrowed in.
“This find will change how we interpret Roman remains and highlights that new information awaits discovery in museum collections.”
Easter is the most important event in the Christian calendar, yet very little is known about when it first appeared in Britain.
Although there is an abundance of popular belief and folklore, we also know next to nothing about the origins of Easter customs, such as the giving of eggs purportedly delivered by the Easter Bunny.
The research team is using evidence from anthropology, archaeology, history, evolutionary biology, law, historical linguistics, natural history and religious studies to try to work out where and when modern Easter traditions first began and when they arrived in Britain.