Mystery and intrigue are inherent to the Holy See. People will always wonder what religious authorities are conspiring to behind closed doors, what treasures lie within the vaults of the Vatican. Despite claims that the Pope has evidence of extraterrestrials and demons tucked away in his catacombs, the truth of the secret archives is much more realistic. Because of this, it is also much more interesting. From handwritten letters of historic personages such as Mary Queen of Scots and Abraham Lincoln to papal bulls excommunicating Martin Luther, the contents of the archives are enough to make any scholar’s eyes go wide. Yet, the high-level nature that makes the contents so fascinating is also what makes them so closely guarded. For in truth, it is not evidence of aliens that the Vatican is hiding from the public eye but rather documents that may show the Church was complicit in Mussolini’s state-sponsored terror and, possibly, even in Hitler’s anti-Semitic pogroms.
The truth behind the secret archives stems from a mistranslation of Latin. The actual name of the Vatican archives is Archivum Secretum Apostolicum Vaticanum. ‘Secretum’ in Latin does not mean ‘secret’ as some may suppose. It is more accurately translated to mean ‘personal’ or ‘private’. The archives are in fact made up of the private letters and historic records of past popes over the past four centuries. The archives were established by Pope Paul V. The Pope clearly had a sense of the historic importance of papal correspondence and knew that such documents should be preserved. However, the 17th century was firmly of the mentality that common people should not be privy to words exchanged by kings and popes. So the archives were kept under lock and key.
Source: What Really Lies Hidden in the Vatican Secret Archives? | Ancient Origins