The Foreign Relations of the United States (FRUS) series is the official diplomatic record and administrative history from the Office of the Historian, U.S. State Department, one of the first three federal agencies established by the founding fathers. Check the status of the series to determine when specific volumes will be published as in many cases material must first go through the declassification schedule before a volume may be released to the public.
There are other versions of FRUS available online either in parts or all of the series: