The rocker is a World War II expert and his research has led him to believe the infamous Austrian was hiding a sexual secret, which may have turned him mad.

"I was born in '48," Ozzy tells "As a kid in England, I used to play on bomb sites. The insanity of it all got me interested.

"If Hitler honestly thought he was going to rule the world with people following him, he must have been f**king insane. He tried to invade Russia... that's, like, four time zones (away). Even with three million men marching, it ain't gonna last (sic)."

But it's Hitler's sex secrets that most intrigue Ozzy: "I always thought he was gay," he chuckles. "Back then, being gay was a criminal offence. When he would go to (vacation spot) Berchtesgaden, his cleaners would check to see if there were any stains on his blankets. And there never were any."