I've been watching a lot of theism vs. atheism debates lately, since I enjoy hearing both sides of this argument a great deal, and have noticed a cross-roads when Hitler gets brought up. On the religious side, I often hear that he was an atheist, and then I almost always hear immediately after by the atheist that he was a Roman Catholic. I don't believe this piece of trivia will prove one particular point over the other, but it did make me realize that I have no real idea, and always just sort of assumed he identified with some sort of religion and I like to sort out the facts when I've caught myself making assumptions.
So, I'm not here to talk about religion specifically, I'm just wondering if historians feel there's a good consensus for Hitler's personal beliefs, or if the jury is still out on that.
edit - Forgive the minor typo in the title. I just noticed that.
Hitler was baptized as a Roman Catholic, and by Catholic rules (then and now) that makes you Catholic. How important Hitler's Catholicism was to him is debatable. You can find all manner of quotes regarding Catholicism and Christianity. Many of those quotes will praise those religions, others will excoriate them. It is more useful to look at Hitler's actions. There, he was a pragmatist.
Roughly a third of his population was Catholic, so he avoided direct confrontation early on. In 1933 the Reichskonkordat was signed between the new German government (with Von Papen as the German signatory) and the relatively new nation of the Vatican City (in existence only since 1929, thanks to the Lateran Concordat). German violations of the treaty started immediately, and there were dozens of protests from the Vatican on that issue. The best treatment of this that I have read is in Ventresca's Soldier of Christ. He explains that while there was a Vatican desire to maintain an independent Catholic Church in Germany (and therefore a desire to not antagonize the German government) there was also a great deal of concern about German violations of the concordat. It must also be noted that the German concordat was worked on for about a decade before Hitler came into power, and that dozens of concordats were signed with many different nations in the interwar period.
For his part, Hitler needed Catholic soldiers so he couldn't push too rapidly against what he saw as Vatican interference. Over time, Catholic influence was marginalized. Priests were harassed by the legal system, often tried for international money transfers (and that priests who spoke out against Nazi practices made up the large majority of such cases was dismissed as a coincidence). Parish newspapers were banned, then the Vatican newspaper, and eventually Vatican Radio was also banned. Catholic youth groups were outlawed and Hitler Youth membership became mandatory.
The biggest flare-ups of conflict between Hitler and the Vatican were March of 1937 and July of 1943. The earlier date is marks the publication of the encyclical Mit Brennender Sorge, which criticized fascism and racism as ideologies. It was a frank papal statement on the matter that had to be smuggled into Germany via motorcycle, then read from the pulpit on Easter. It was immediately banned and the Nazis tried to destroy any copy they could. 1943 inflamed the idea that the pope was too supportive of the Allies, and possibly should be moved out of Italy and into Germany (since Italy had just effectively bowed out of the war and the Allies were marching up the Italian peninsula). Just how concrete these plans were is a matter of some conjecture, but they clearly didn't go forward with them.
In short, Hitler desired to undermine religion when he could to advance his plans, but was unwilling to make a formal break because he needed Catholics to pursue those same plans.