Father Gabriele Amorth believed that Stalin and Hitler were possessed by the devil. Although the media’s reporting of it made the public think Amorth was giving an excuse for their actions (heaven knows the Vatican is always getting accused of sympathising with the Nazis and other dictators), I believe Father Amorth. It isn’t so much that “the devil made them do it,” but rather that they made pacts with the devil that enabled them to unleash so much horror.
So my question is, what were the other signs that these men were possessed? Hitler practised the occult, we know that. But what other evidence is there? I’m unaware of Stalin practising the occult.
As far as I know, there are no reports of them having superhuman strength, knowledge of hidden things or speaking in languages they shouldn’t know.