It must be clearly understood that the collection microfilmed at the Berlin Document Center does not reconstitute intact that part of the Hauptarchiv which escaped destruction. No catalogue of the original archival holdings had been preserved, and the only remaining clues to the contents are surveys and lists drawn up between 1942 and 1945. These include itemised lists of holdings on particular topics (nationalist parties, Marxist parties), lists of documents, contained the Hauptarchiv’s own files (Folders 1923 I and II). The most important evidence is contained in the “Bestandbuch Archivalien Hauptarchiv, “which lists the documents, files, and groups of files (Aktenkoerper) as they were received at the evacuation depot in Neumarkt-St. Veit between August 1, 1944 and March 1945.   On the basis of these lists, statements of the Hauptarchiv’s last director (Dr. Bruegmann), it must be concluded that the bulk of the material was rescued. There are notable exceptions, such as the extensive files of the Wehrpolitisches Amt, the Rechtswahrerbund, the Allgemeiner deutscher Gewerkschaftsbund, and the Reichs-Fluechtlingshilfswerk –all of which have disappeared. The same holds true for the important file on the plot of July 20, 1944, of which there remains only the carefully itemized curator’s list of 126 documents. It seems certain that some other individual pieces have been accidentally destroyed or purposely eliminated. 

There is no evidence that the material which reached the Berlin Document Centre was ever given a definitive over-all organisation at the Hauptarchiv itself, a fact which is not surprising in view of the recent date of its acquisition, its rapid expansion, and the disarray caused by the transfers to the storage sites. The final transfer to Berlin must have compounded the confusion. Consequently, the Berlin Document Center was obliged to undertake the reorganization of the material. Most of this work was done in 1946 and 1947; minor additional reorganisation was carried out in 1959. Wherever possible, the identifiable folders of the Hauptarchiv were maintained and the original headings used. No attempt was made to use folders of uniform length. Thus folders may contain a few sheets or several thousand. The Berlin Document Center, on its own, assigned numbers to each folder for easier handling. At the same time it proceeded to set up a broader scheme which took into account the nature of the material at hand.

The material which the Hauptarchiv itself had received from the various NSDAP organization and from individual donors or collected on the basis of questionnaires and research was divided roughly into 28 groups (or Gruppen, as the Berlin document Center called them under topics such as personal documentation on Hitler, early NSDAP history, recollections of old militants, political parties, citizens’ militias, Germans abroad, and so forth.

A different procedure was adopted for the remainder of the material, which had apparently been stored in separate filing cabinets at the Hauptarchiv. This consisted of documents supplied by the various government, police, and judicial agencies. No attempt was made to impose topical groupings, and the material was organized roughly by provenance – that is, by whatever agency had turned the files over to the Hauptarchiv. The files of the Berlin police, which are to be found in Group 'Verschiedenes', constitute the only important exceptions. The main agencies are the Munich police, the Bavarian Ministry of the Interior, and the Munich tribunal. Unfortunately, additional material of the Munich and Nuremberg police, which was located in 1959, could not be filmed along with the bulk of the material from these sources; it appears in a later part of the microfilms. The Hauptarchiv’s own working files bring the microfilm to a close. 

The catalogue follows the scheme of the “Collecton NSDAP Hauptarchiv” of the Berlin Document Center. Folders 1-1421 constitute MF Doc 29/1 and are arranged into 29 subject groups supplied by the Berlin Document Center.  Folders 1426-1923 II constitute MF Doc 29/2 and are arranged by provenance, that is, by the agency heading indicated at the Berlin document Center. 

As no frame numbers were assigned at the time of the filming and the folders are of very unequal length, the Hoover Institution has supplied an approximate count of frame numbers per folder (usually on side of a page, sometimes both sides).

The content heading for each folder (in German) was drawn up by the Berlin Document Center and is reproduced intact as it appears at the beginning of each folder. Where this heading was insufficient or misleading for the microfilm user, more detailed descriptions (in English) have been added at the Hoover Institution, as have cross references and technical information. Whenever a reference to related material seemed necessary, the word “consult” was used. The German abbreviations were not corrected even when inconsistent, but were kept as they appear on the film.

The problems of microfilming large amounts of material widely divergent as to shape, size, state of preservation and provenance are readily apparent. In order to solve some of these problems, three different methods were chosen. The greater part of the material was filmed on a rotating camera (flow camera) which filmed automatically both front and back pages. MF Doc /1 (excluding reels with suffix 'A' or 'B') were filmed in numerical sequence in this manner. A considerable body of material, either bound or too bulky in size to be filmed by the rotating camera, was filmed with a flat-bed camera which reproduced each page individually. Therefore entire folders or parts of folders had to be removed from the sequence and filmed by the flat-bed camera. Reels with suffix 'A' were filmed in this manner. In a few isolated cases the material was in such bad condition that is could not be microfilmed; it was photostated instead and the Photostats were then microfilmed under special conditions at Standford. Reel B covers this material. Whenever material was removed from Reels 1-96 for technical reasons, a notation was made as to its new location. For example, the notation “MF Doc 29/1/1, Folder 2: Briefe an Hitler A-Z / See also MF Doc 29/1/1A” indicates that part of the material in the folder was shifted to Reel 1A. If the entire contents were removed, the notation would be\"MF Doc 29/1/1, Folder 5: Personalakte Adolf Hitler…- See Reel B.” On the average, reels contain between 90 and 115 feet of microfilms, with approximately 2, 000 frames for the rotating camera (Reels 1-96) and 600 – 1, 000 frames for the flat-bed camera (Reels 1A-37A). It must also be noted that in the course of microfilming a considerable number of folders were split between the end of one reel and the beginning of the next. The Hoover Institution has 134 reels (1-96, 1A-37A, B) of negative microfilms and an equal number of positives. The National Archives also hold a complete set of positives.