There is controversy over Hitler’s religion. Some say he was Catholic, since he was baptized Catholic. Some say he was pagan, since the Nazi Party’s ideologues were openly pagan. Some say he was an atheist, based on what he said in private as recorded in Hitler’s Table Talk.
I think that last is conclusive. What Hitler said in public speeches was surely calculated for public appeal, not a reflection of his own views. What he aid in private wold be his real opinion.
But even if Hitler cannot be decisively identified as an atheist, Mussolini can. He even published a pamphlet titled “God Does Not Exist.” Religion, he wrote, was a mental illness to be dealt with by psychiatrists.