Brown hares and chickens were revered as gods rather than reared for food when they were first introduced to Britain in the iron age, archaeological analysis suggests.

In research that shows modern-day Easter festivals were not the first to celebrate chicks and bunnies, a team of experts from the universities of Exeter, Leicester and Oxford have found evidence that the animals were buried with care and intact in the period that preceded the Roman invasion of Britain.

Historical evidence suggests Britons of the period associated the animals with deities and considered them too special to eat. Commentarii de Bello Gallico, Julius Caesar’s firsthand account of the Gallic wars, says “the Britons consider it contrary to divine law to eat the hare, the chicken or the goose. They raise these, however, for their own amusement or pleasure.”

Radiocarbon analysis of hare and chicken skeletons from a number of sites in Hampshire and Herefordshire backs up that assertion, showing that the two species were introduced simultaneously to Britain between the fifth and third centuries BC. Excavation has previously revealed the animals had been carefully buried without being butchered.

Prof Naomi Sykes from the University of Exeter, who is leading the research, said: ““Easter is an important British festival, yet none of its iconic elements are native to Britain. The idea that chickens and hares initially had religious associations is not surprising as cross-cultural studies have shown that exotic things and animals are often given supernatural status.

“Historical accounts have suggested chickens and hares were too special to be eaten and were instead associated with deities – chickens with an iron age god akin to Roman Mercury, and hares with an unknown female hare goddess. The religious association of hares and chickens endured throughout the Roman period.

“However, archaeological evidence shows that as their populations increased, they were increasingly eaten, and hares were even farmed as livestock. Rather than being buried as individuals, hare and chicken remains were then disposed of as food waste.”

The cross-disciplinary academic team, whose objective is to investigate the origins of Easter traditions and the animals that have come to be associated with it, has previously revealed that the first rabbits were introduced to Britain not by the Normans, as was previously thought, but by the Romans, who arrived in the first century AD.

Hares and chickens were both farmed for food during the Roman occupation of Britain, but in the economic collapse following the Roman withdrawal in 410AD rabbits became locally extinct and the populations of chickens and brown hares crashed.

Historical and archaeological evidence show rabbits were reintroduced to Britain as an elite food by the Normans in the 11th century. Rabbits were increasingly common in the 19th century, probably contributing to their replacement of the hare as the Easter bunny when the festival’s traditions were reinvigorated by the Victorians.