War Department Decimal File System

The United States War Department produced multiple editions of the War Department Decimal File System, beginning in January 1914. The department used the system to classify correspondence, decimal files, and other records.

• War Department Correspondence File: A Subjective Decimal Classification...,
  July 1917
  (Reprint of January 1914 Edition) [13.55 MB download, 331 pages]
  
  
• War Department Decimal File System, 1943 (Revised Edition) [20.57 MB download, 432 pages]
  
  
• Additional Classifications [15 KB download]

Additional Resources:

• See descriptions in the National Archives Catalog for records arranged according to the War Department Decimal File System
  
  
• Military and Wars