A question concerning hitler and his mental health.?

Well i can not say i am an expert when it comes to hitler and the nazi party. But i know he was a very very intelligent man. And it bothers me when i hear of such an intelligent person commiting such atrocities. How could such a brilliant man be so racist and ignorant. These are trait's usually of weaker minded people. Who have been taught these traits during child hood. But im pretty sure hitler grew up in a jewish family am i right so that can not be the case. Do you think maybe he looked at jews as some people look at neo conservatives. Ignorant people that the world would be better off without. I feel this way about religion but the people it influences i would never feel any anger towards besides just disagreeing with them. Is it likely though it was not really against the jews but mostly against religion itself and he thought he was doing it for the better good. And that he was not just killing people for the hell of it.