The bones had been discovered during the 1957-67 excavation at Whithorn Priory but who they belonged to was a mystery.

New research, funded by Historic Scotland, has used the latest scientific techniques to work out when the men died, who several of them were, where they came from and even what they ate.

Peter Yeoman, Historic Scotland senior archaeologist, said: “We are absolutely delighted by the results from this project.

“It is remarkable to be able to put likely names to people who died more than 600 years ago.

“This has been a rare opportunity to build up a picture of life and death among Scotland’s rich and powerful churchmen of the Middle Ages.”

A variety of techniques were used to identify the eight bishops.

In four cases radiocarbon dating of the bones provided vital evidence as it gave precise information about when the people had died.

This was a huge advance from the 50s and 60s.

At that time the graves were identifiable as those of senior ecclesiastical figures but being more exact was fraught with problems.

Mr Yeoman said: “Very fine gilded altar vessels, a gold pontifical ring, and the remains of a wooden crozier were found with the skeleton in the central grave, all of which showed he was a bishop.

“But it was only when we had the radiocarbon dating that we were able to say it was probably bishop Henry who died in 1293, who had been important in rebuilding parts of the priory after it was raided and damaged by soldiers in 1286.”

Analysis also showed that Henry had been suffering from tooth abscesses.

While some mysteries were solved others have emerged.

The bishops were in an especially holy area between the high altar and the shrine of St Ninian – the man credited with bringing Christianity to what later became Scotland.

Divine grace radiating from his relics was thought to help wash away the sins of anyone who came into contact with it.

Mr Yeoman said: “To be buried in that spot was a very special privilege and largely for senior churchmen.

“It was like being put on the expressway to heaven, that would take you straight through purgatory.

“But one of the skulls belonged to a man who had a severe cleft palate and who would have had a serious speech impediment.

“It’s hard to imagine he would have been able to carry out the functions of a bishop, such as preaching sermons, in that era.

“So, who was he to have been awarded such an honoured burial place?”

The finds made during the excavation are all in the collections of National Museums Scotland.

Dr David Caldwell, National Museums Scotland keeper of Scotland and Europe, said; “This is a very important piece of research and the museums are happy to be working with Historic Scotland on this project.

“This research is revealing new information about some of the key items relating to the bishops.”

Keeping the finds in storage, to minimise deterioration, kept them safe while research techniques advanced and may mean that future archaeologists will be able to learn even more from them.

Dr Chris Lowe, director of Headland Archaeology Ltd, said “It is tremendous to be able to use modern techniques to analyse the skeletons excavated by an earlier generation of archaeologists.

“The insights we have gained represent a very important step forward in our understanding of the lives and lifestyles of our medieval ancestors.

“Back in the 1960s it would have been difficult to imagine that it would one day be possible to identify the people whose graves they had excavated, let alone work out where they came from, what they ate and the diseases they suffered from.”

Case study: Named Again After 700 Years (pdf)

• Whithorn Priory and Museum are in the care of Historic Scotland. They are in Whithorn on the A746. Telephone 01988 500508.
  
  Visit www.whithornpriorymuseum.gov.uk for additional information on the property and its history.
  
  
• The research was carried out by Edinburgh-based Headland Archaeology on behalf of Historic Scotland.
  
  
• All the finds from the excavation are part of the collections of National Museums Scotland and were released on special loan for the purposes of the research project.
  
  
• The recent research project was the first time Scottish archaeologists have had an opportunity to gather detailed data on a group of high status individuals from the Middle Ages.
  
  
• Radiocarbon dating helped identify the graves of bishops Walter (d. 1235), Henry (d. 1293), Michael (d. 1359) and Thomas (d. 1362).
  
  
• Other bishops identified were Gilbert (d. 1253) and Michael (d. 1359).
  
  
• The central grave was being used for a second time and had originally been the burial place of bishop John (d. 1209).
  
  
• Analysis shows that the bishops had all probably come from southern Scotland or maybe Cumbria – at this time the church in Galloway fell under the archdiocese of York.
  
  
• Dietary evidence indicates that they enjoyed high quality meat and fish – including large sea fish like cod. In the case of bishop Walter, his rich diet made him clinically obese and caused diabetes.
  
  
• One of the most impressive finds from the excavation was of a gilded and enamelled crozier head of a type that dates from around 1175. The grave also contained brocade threads from vestments, gilded sequins from his headdress, and silver altar vessels. This has now been identified as the grave of bishop Simon (died 1355), meaning the crozier was an antique when buried.
  
  
• The excavation took place in the eastern area of the priory church which bishop John had enlarged around the start of the 13th century.
  
  
• Bishops of Whithorn included the whole of Galloway with its rich farmlands in their diocese.