The graves of dozens of what may have been early British kings, queens, princes and princesses from the era of the mythical King Arthur have been revealed by a new study.
It suggests that British royal graves dating from between the fifth and the seventh centuries A.D. have been overlooked until now, possibly because they weren’t elaborate and contained no valuable grave goods.
The research reconsiders archaeological evidence from a little-understood period of British history, between the end of Roman rule and the late Anglo-Saxon kingdoms — a time traditionally described by the legends of King Arthur.
The new study by Ken Dark, an emeritus professor of archaeology and history at the University of Reading in the United Kingdom, identifies what may be up to 65 graves of post-Roman British kings and their families at about 20 burial sites across the west of England and Wales, including the modern English counties of Somerset and Cornwall.
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The British continued to rule in what are now the west of England, Wales, and parts of Scotland in the centuries after the end of Roman rule in Britain in the early fifth century, while the invading Anglo-Saxons settled in the east.
But while Anglo-Saxon rulers of the time were given elaborate burials with valuable and ornate grave gifts, the Christian British may have viewed this as a pagan practice, Dark said.
Instead, the British seemed to have buried their royalty without grave goods in simple graves without stone inscriptions alongside the graves of common Chistians – although many of the royal graves were enclosed by a rectangular ditch and probably surrounded by a fence that has since rotted away, he said.
Dark, who is now at the University of Navarra in Spain, is the author of the study published this month in the Journal of the Royal Society of Antiquaries of Ireland.
"The royal graves are very standardized," he told Live Science. "They have some variation, just like the ordinary graves do — some are bigger, some are smaller, some have only one grave in the center while others have two or three."
Roman rule in Britain lasted from A.D. 43, following a Roman invasion under the emperor Claudius, until about A.D. 410, when the last Roman troops were recalled to Gaul (modern France) amid internal rebellions in the Roman Empire and invasions by Germanic tribes. (The Roman general Julius Caesar invaded southern Britain in 55 B.C. and 54 B.C., but he didn’t establish permanent Roman rule.)
Between the fifth and seventh centuries, the Christian British ruled what are now western England and Wales as a patchwork of small kingdoms that tried to continue Christian Roman traditions. In the same period, pagan Germanic tribes — the Angles, Saxons and Jutes, who originated in the north of Europe — invaded and settled in the eastern parts of the country.
The legends of King Arthur, who was supposedly British and Christian, are set in this period, although most historians think Arthur didn't actually exist. (Dark, however, suggests that a real person or a fictional hero of that name was famous as early as the sixth century, because Dark's previous studies have suggested there was a sudden spike in the use of the name "Arthur" among British and Irish royal families at the time.)
Dark began his investigation to address a long-standing archaeological mystery: while many British kings were known to have lived during this time period, almost none of their graves had ever been found.
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Until this study, the burial of only one British king from this era was known after being discovered in the northwest of Wales; an inscription on a gravestone names the person buried there as Catamanus (Cadfan in Welsh) and declares that he was a king (rex in Latin.)
But Cadfan may have retired from the kingship to become a monk before his death, and the phrasing of the inscription implies his grave was being commemorated because of his status as a monk, Dark said.
Meanwhile, the graves of at least nine Anglo-Saxon rulers from the period have been found, including one at the famous ship-burial at Sutton Hoo near the east coast of England.
To get to the bottom of the mystery, Dark reviewed the archaeological work previously done at thousands of burial sites from this period in the west of Britain and Ireland.
His study suggests that the British royal graves were placed within early Christian cemeteries; and while they were marked out as those of high-status people, they seem very humble compared to ornate pagan graves and none have stones with inscriptions stating who was buried there.
The outer enclosures vary in size and some contain up to four graves, but they are typically about 15 to 30 feet (4 to 9 meters) across and up to 30 feet (9 m) long.
"We've got a load of burials that are all the same, and a tiny minority of those burials are marked out as being of higher status than the others," Dark said. "When there are no other possible candidates, that seems to me to be a pretty good argument for these being the ‘lost' royal burials."
At one site at Tintagel, a fortified peninsula on the coast of Cornwall that's long been associated with post-Roman British royalty and legends of King Arthur, what are thought to be five British royal graves in an early Christian cemetery take another form. Each was covered by a mound of earth, possibly because Irish royal graves are also covered with mounds called "ferta," he said. (The post-Roman British had strong links to Celtic Ireland; the ancient Irish and British were both of Celtic origin and had similar languages.)
But the pattern of placing the royal graves at the center of an enclosure – usually rectangular, but sometimes circular – appears to be a burial style developed by Christians in late Roman Britain, he said.
"The enclosed grave tradition comes straight out of late Roman burial practices," he said. "And that's a good reason why we have them in Britain, but not in Ireland — because Britain was part of the Roman empire, and Ireland wasn't," he said.
Although previous studies had noted the enclosed graves were thought to hold people of a high social status, rather than royals; and archaeologists were expecting royal burials to be covered by mounds of earth or marked with inscriptions on stone, he said. "But I'm suggesting that this burial practice was specifically royal."
Originally published on Live Science.
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Tom Metcalfe is a freelance journalist and regular Live Science contributor who is based in London in the United Kingdom. Tom writes mainly about science, space, archaeology, the Earth and the oceans. He has also written for the BBC, NBC News, National Geographic, Scientific American, Air & Space, and many others.