Records of the Office of War Information (RG 208)
This agency formulated and implemented information programs to promote, in the United States and abroad, understanding of the status and progress of the war effort and of war policies, activities, and aims of the U.S. government. Most of the records date from 1942 to 1945, although there are some files of predecessor agencies such as the Office of Facts and Figures, the Office for Emergency Management, and the Coordinator of Information.
National Archives Preliminary Inventory NC-148: Records of the Office of War Information, prepared in 1967 and updated in 2018, describes the records of the OWI and predecessor organizations in more detail.
You can search the National Archives Catalog for entries from RG 208 or see a description in the Guide to Federal Records.