More than 700,000 records relating to WWI, as well as photos, films and audio recordings were made accessible on a new portal on the Federal Archive's website.
The collection includes private material as well as files of military and civilian authorities, records left by politicians and military officers, documentaries and propaganda films. Access to the complete archive is free.
The archive will also help people compiling family histories, say curators, since it has extensive information about locations where individual soldiers served. It also contains letters written to and by combatants in the war, which began on July 28, 1914, and ended on November 11, 1918.
The war pitched the Allies, including Britain, France and Russia, against the Central Powers of Germany and Austria-Hungary and their allies, resulting in more than 37 million casualties.
Although there is still much debate about the causes of the conflict, Germany has been largely blamed for its outbreak and as a result has been closely scrutinized over its plans for the 100-year anniversary.
Commemorations will be low-key in Germany, with no large public ceremonies of national remembrance.
Instead, the government has provided financial assistance to various civil society and international events planned through the year.
One of these is an exhibition called "1914 – 100 years afterwards" at the German Historical Institute in Berlin.
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