(CNN) Meat-heavy banquets have long been thought to be a common feature of early medieval life for England's kings and nobles, who are often depicted feasting on legs of animal flesh and knocking back goblets of ale in the great halls of their realm.
However, a new study that examined the dietary signatures contained in bones of more than 2,000 skeletons has cast doubt on this assumption, finding that most Anglo-Saxons ate a diet rich in cereals and vegetables and low in animal protein -- no matter what their social status.
Archaeologists were able to glean this information by analyzing the presence of different isotopes, or variants, of the elements carbon and nitrogen in bone collagen. Bones preserve an isotopic record of the different types of food an individual consumed over time. The study mainly looked at ribs, which represent a period of 10 years before a person's death.
"Basically, what I do is I get bones from skeletons, dissolve them in acid, make them squishy and work out what people ate," said study author Sam Leggett, an early career fellow at the School of History, Classics and Archaeology at The University of Edinburgh in Scotland.
"You can tell roughly how much animal protein, not just meat, but any kind of animal protein -- eggs and dairy as well."
Historians had long assumed that Anglo-Saxon elites ate far more meat than the peasantry they lorded over because of documents itemizing food tributes, known as "feorm" in Old English.
These texts, some of the very few written documents available from that time, list in great detail the foods that were owed by peasants to royal and noble households. It was thought that these lists represented a typical elite diet.
One such food list compiled during the reign of King Ine of Wessex (688-726 AD) listed supplies that amounted to 1.24 million kilocalories -- over half of which came from animals -- including mutton, beef, salmon, eel and poultry, as well as cheese, honey and ale.
The researchers calculated that each household member would have received 4,140 kilocalories from the meal -- the equivalent of Thanksgiving dinner and then some.
Rather than food that was collected and eaten regularly by royal households, these lavish feasts were exceptional events, the study of the isotopic data suggests.
"When we calculated how many calories (the food tributes contained) it was so high that even if they were having (these feasts) twice a month that could not give the signatures I was seeing," said Leggett, who completed the research while a doctoral student at the University of Cambridge in the United Kingdom.
"That meant the majority of what these people were eating had to be mostly plant based with a small amount of animal protein. There were some people who fell in the zone of a modern vegan," she said, adding that most of the people studied would have been equivalent in today's terms to vegetarians, who eat eggs and dairy.
The study upends many assumptions about Anglo-Saxon society, which was thought to be very hierarchical. The banquets could have been community-building events involving hundreds of people, researchers suggest.
"Historians generally assume that medieval feasts were exclusively for elites. But these food lists show that even if you allow for huge appetites, 300 or more people must have attended," said study coauthor Tom Lambert, a fellow and director of studies in history at Sidney Sussex College at the University of Cambridge, in a blog.
"That means that a lot of ordinary farmers must have been there, and this has big political implications."
The research was published in the journal Anglo-Saxon England in April.