A mass grave containing the remains of more than 400 British and Australian soldiers killed in the bitter fight for Fromelles, near Lille, in 1916, has been discovered by Scottish archaeologists exploring the First World War battlefield.

The allied casualties had been buried by German forces in the mass grave, but its location was then lost until clues appeared in a survey conducted by archaeologists last year.

After the war the names of the men were added to the memorials of the tens of thousands of Western Front dead with no known grave.

For almost two weeks, Tony Pollard, director of the Centre for Battlefield Archaeology at the University of Glasgow, and his team of 15 international experts have been uncovering the dead of Fromelles - a military and human disaster that began on July 19, 1916, as an attempt to divert German resources from the Somme offensive 50 miles to the South, and ended a day later in defeat.

Until now the exact location of the grave was unknown and the ground has lain undisturbed since 1916.

Dr Pollard now believes that his team has located the bodies of about 400 British and Australian troops killed during the battle and buried at a site known as Pheasant Wood.

“This is probably the most important job I have ever done,” Dr Pollard said. “The speculation is over: the dead of Fromelles are in Pheasant Wood.”

The team found the first human remains within 24 hours of beginning their excavation. They have now unearthed eight separate pits covering an area 130m (425ft) long and 30m (100ft) wide.

Although Dr Pollard was reluctant to be drawn on the total number of bodies they have discovered, he confirmed that it was in the hundreds and that the graves seem to be intact.

“We have continued to make discoveries and now have quite a substantial number of remains,” he said. “The evidence strongly suggests that the pits have been undisturbed since 1916.”

He said that finding the graves had been an emotionally distressing experience. “There was a degree of relief that our hard work had come to fruition but that was tempered by the shock and sorrow of what we were seeing - these are dead men who died in battle,” he said. “You cannot help being moved.

“We have completed in reverse the same task as the German soldiers, so we know that it must have been a nasty job,” Dr Pollard added. “The clay is difficult to dig, they were working in the height of summer, and then they had to bury the bodies.”Among the team are five members of the Glasgow University archaeological research division, as well as Australians, Americans and a Spaniard. They are using a small mechanical excavator to remove the top layers of soil, but must recover the remains by hand. Although some of the experts excavated mass graves in Bosnia, and helped to search for bodies after the 9/11 terrorist attacks in New York, Dr Pollard said that they had found the dig in France especially harrowing.

“Even though our team is incredibly skilled and have global experience in this field they were still overwhelmed,” he said.

The Battle of Fromelles was an unmitigated disaster for the Allies. After the British and Australians launched an assault on heavily fortified positions in daylight they suffered heavy losses. More than 5,000 Australian troops were killed, captured or injured, while there were a further 1,500 casualties on the British side. According to German records, about 400 soldiers were buried at Pheasant Wood.

Over the next week the group will try to find evidence to confirm the nationalities of the dead, and a decision will be taken over what is to be done with the site. If identification becomes possible, some families may wish to repatriate their relatives.

Dr Pollard, an international expert who has conducted pioneering work in battlefields from North Africa to Culloden, said that he hoped that their research would change perceptions of the First World War, and keep the memories of it alive as the remaining survivors die.

“I'm hoping it will bring about the idea that the Great War was a global event, that it did not just involve Britain, and that it was a more complex event than we gather from snapshots on film and television,” he said.

“As veterans are leaving us almost to a man it is archaeology that is going to reinforce the memories.”

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