Details of works of art that were looted by Nazi Germany are being listed on an international database so the items can be traced.
It is hoped that publishing the documents online will help families and historians find missing items seized by the Nazis.
The National Archives and the Commission for Looted Art have signed an agreement to provide the documents.
The files, dated between 1939 and 1961, feature inventories and images of art.
The BBC reports the records also include details about efforts to identify and recover the articles during and after World War II.
Last year, the Leopold museum in Austria agreed to pay $US19 million to a Jewish art dealer's estate for an Egon Schiele painting, Portrait of Wally, that the Nazis had stolen from her.
The museum has now announced it will sell another of the artist's works to repay a loan it took out to cover the costs of a 12-year legal battle.