By Ray Furlong
BBC News, Bad Arolsen, Germany
The world's largest archive of Nazi German documents will be opened to historians for the first time, after an agreement reached by the 11 countries that control it.
The archive at Bad Arolsen will still be used to trace Nazi victims
The announcement was made after two days of talks by diplomats from the 11 countries, who were meeting in Luxembourg.
For six decades, the archive - housed in a storeroom in the sleepy Baroque town of Bad Arolsen, in central Germany - has been used exclusively by a Red Cross agency that helps people trace loved ones who went missing during World War II.
It has taken several years of negotiations to reach this agreement, and the talks in Luxembourg also went on later than expected as diplomats discussed the details of the deal.
It means historians will for the first time gain access to the files, which contain personal details on more than 17 million people who went through the concentration camp and slave labour system.
Brutal raw facts
The archive is a treasure trove of stories, most of them tragic.
Among the stacks of yellowing pages, we found the file of a man arrested by the Gestapo in 1939 for smuggling Jews out of Nazi Germany, and into neighbouring Switzerland.
Just 21 years old, he was despatched to a concentration camp and forgotten by history.
Another file notes the date of birth of a young Polish girl, and then her date of death, three months later, at a concentration camp. There is no emotion, just brutal raw facts recorded on paper by bureaucrats.
The death books of the concentration camps note with punctilious attention to detail the date and time of death, as well as the cause. But the documents can also tell lies.
Archivist Udo Jost showed us the book from the Matthausen camp, which showed that hundreds of Russians termed "political prisoners" by the Nazis had died on 20 April, 1942.
The cause of death was filed as "shrapnel from bombing". But the fact that the men died precisely every second minute, on Adolf Hitler's birthday, suggests they were really killed on the commandant's orders.
"Or take a case of a Catholic priest who denounces the deportations of Jews from the pulpit," Mr Jost said.
"He could be arrested by the Gestapo, and they could put in his file that he was molesting the choir boys."
'History's dark chapter'
Many of the advocates of opening the files recognise these dangers.
"It's important to have regulations controlling access to this information," said Deidre Berger, head of the American Jewish Committee's Berlin office.
"The Nazis were interested in defaming and slandering a lot of their victims."
The details of some 17 million people are contained in the files
The agreement in Luxembourg promises adequate protection of personal data will be considered. Details of how this will work will be released later.
The World Jewish Congress (WJC) welcomed the decision to offer greater access to the archives as a powerful step toward stopping Holocaust denial.
"We are pleased that after 60 years, the millions of written proofs for the Nazi mass murder against Jews will be open for researchers," Israel Singer of the WJC said in a statement from New York.
"It is a strike against all those Holocaust deniers. The opening of the archives is necessary to continue research into this dark chapter of our history.
"It is necessary to preserve the past so future generations could learn a lesson from it."
Archivists say the information in the files will not dramatically revise what is already known about the Holocaust, but will provide a rich additional source of detail.
The archive will continue to serve the purpose it was originally created for after the war - tracing missing persons.
Last year, there were 150,000 new requests for information about relatives who went missing during the war and the Holocaust.