The database, which is searchable via the CIA Records Search Tool (CREST), contains information from the 1940s to the 1990s, including reports from the Korean War and the Vietnam War.
The CIA had planned to publish the documents at the end of 2017, but finished the work ahead of schedule. The agency began the project following a Freedom of Information Act injunction launched in 2014 by Muckrock, a non-profit news organization.
"Access to this historically significant collection is no longer limited by geography. The American public can access these documents from the comfort of their homes," Joseph Lambert, CIA Director of Information Management, said.
However, not everybody is convinced that the documents in the CREST database are genuine. Security expert Dmitry Efimov, a member of Moscow Council's Advisory Committee on Security, told Radio Sputnik that he suspects many of the files are fakes.
"I think this was published on the personal orders of CIA Director Brennan, a famous neocon who is leaving along with Obama and who is probably using this opportunity to create a new stream of misinformation," Efimov said.
"Particularly since there is no such thing as the whole truth, there is the truth which is present in the CIA's real documents, which of course exist, but I think that a lot of work has been done to falsify a huge number of documents in this batch and change the relationship to the Vietnam War, for example."
Commenting on the release, CIA spokesperson Heather Fritz Horniak insisted that the documents, which appear redacted, are genuine and were not released on a selective basis.
"None of this is cherry-picked," Horniak said.
"It's the full history. It's good and bads."
However, Efimov claims that the release is an attempt by the CIA to rewrite history in order to assist its political ambitions.
"The main objective of the US is the spread of liberal American democracy around the world despite the objections of the receiving country. It is in this respect that history will change, there will be new documents which don't have sources. But the presence of a large number of hidden sources in certain documents on a specific topic says that here (in the declassified CIA documents) someone has edited the past very well."
This kind of disclosure is a way to distract attention from political topics, Efimov said.
"Disclosure of the 'Stargate' CIA program is a wonderful theme, a great way to divert the consciousness of American society away from real problems. Just imagine how you can use that topic on CNN, in order to bring it to the attention of all American housewives. I don't exclude the possibility that some more fine papers will appear, some kind of reports about something, which predicted something, we will get the names of some new American prophets. That is, the construction of a mythical American history that will distract the attention of Americans," Efimov said.