The Nazi leader was imprisoned there following the unsuccessful Beer Hall Putsch of 1923, when Hitler tried to seize power in Bavaria.
German historian Peter Fleischmann, who heads the Bavarian state archives in Nuremberg, says a review of prison records reveals Hitler and fellow members of the Nazi Party "had their path greased for them" compared to other inmates.
Fleischmann said today the records, some of which were missing for decades, show Hitler received 330 visitors during his year at Landsberg.