Over the years, I've heard from quite a few people who wished to take me to task over what I say on this site, especially about Atheism vs. Christianity. One of the common cheap-shots taken by the more belligerent of these people is to claim that Hitler was a Christian. This appears to be a very common belief among atheists (or at least a very common lie they spread), but it is also very easily disproved by what Hitler himself said during and after his rise to power.
So that settles it, right? Hitler claimed to be a Christian, so that means anti-Christians can forever bash us over the head as being of the same religion as Hitler, right? Let's examine another claim of Hitler, that he was a good buddy to France:My feeling as a Christian points me to my Lord and Savior as a fighter. It points me to the man who once in loneliness, surrounded only by a few followers, recognized these Jews for what they were and summoned men to fight against them and who, God's truth! was greatest not as a sufferer but as a fighter. In boundless love as a Christian and as a man I read through the passage which tells us how the Lord at last rose in His might and seized the scourge to drive out of the Temple the brood of vipers and adders. How terrific was his fight against the Jewish poison.-Adolf Hitler, in a speech at Munich, April 12, 1922 
So I guess Hitler was also a great peace maker in Europe... y'know, because he claimed to be. The fact is that Hitler was a master deceiver. He knew he had to rally the entire populace to his ideals if they were to support his world-conquering war machine, and that he could never do that if he openly admitted his hatred for Biblical Christianity and his desire to destroy the church. So Hitler did what any good, ruthless politician in his position would do: he publicly appeased the church, while privately plotting its elimination.I think I can assure you that there is no one in Germany who will not with all his heart approve any honest attempt at an improvement of relations between Germany and France. My own feelings force me to take the same attitude.... .The German people has the solemn intention of living in peace and friendship with all civilized nations and powers.... .And I regard the maintenance of peace in Europe as especially desirable and at the same time secured, if France and Germany, on the basis of equal sharing of natural human rights, arrive at a real inner understanding....The young Germany, that is led by me and that finds its expression in the National Socialist Movement, has only the most heartfelt desire for an understanding with other European nations.-Adolf Hitler, in a letter to French fascist Hervé [Der Fuehrer, p. 414] 
So to answer the question "was Hitler a Christian": no. He may have given a pretense of piety and cooperation with the church, but in his real opinions and in his actions it is obvious he was not a follower of Christianity. To be fair, he wasn't an atheist either, as some claim -- he apparently did have some kind of spirituality, most likely centered around himself as a twisted Nazi messiah:I'll make these damned parsons feel the power of the state in a way they would have never believed possible. For the moment, I am just keeping my eye upon them: if I ever have the slightest suspicion that they are getting dangerous, I will shoot the lot of them. This filthy reptile raises its head whenever there is a sign of weakness in the State, and therefore it must be stamped on. We have no sort of use for a fairy story invented by the Jews.-Adolf Hitler, Hitler's Table Talk, p. 6-7 The heaviest blow that ever struck humanity was the coming of Christianity. Bolshevism is Christianity's illegitimate child. Both are inventions of the Jew. The deliberate lie in the matter of religion was introduced into the world by Christianity.-Adolf Hitler, Hitler's Table Talk, p. 6-7 Astuteness; the ability to lie, twist, cheat and flatter; the elimination of sentimentality or loyalty in favor of ruthlessness were the qualities which enabled men to rise; above all, strength of will. Such were the principles which Hitler drew from his years in Vienna...He learned to lie with conviction and to dissemble with candor.-Hitler, a Study In Tyranny, p. 36-37 
While I don't think Hitler was a true atheist, believing that there is no God and no spirit world, much of what he said and believed is eerily similar to the mantras of modern-day secular humanism:As time went on, it became clearer that he was thinking of himself as the Messiah and that it was he who was destined to lead Germany to glory. His references to the Bible became more frequent and the movement began to take on a religious atmosphere. Comparisons between Christ and himself became more numerous and found their way into his conversation and speeches.-A Psychological Analysis of Adolph Hitler 
After taking a careful look at the words and actions of Hitler, it's clear that the closest one can associate him with Christianity is that he gave lip service to the faith when it was convenient for his political image. However, his true feeling was much more like the secularists and atheists who try to attack Christians by lumping us in with this historical monster: that Christianity is an obstruction, a relic that needs to be done away with to make room for a grander philosophy. Even when Hitler tried to hijack Christian scripture and belief and inject his own twisted ideals into it, the result was quite antithetical to anything found in the Bible. So whose beliefs are really more like Hitler?So it's not opportune to hurl ourselves now into a struggle with the Churches. The best thing is to let Christianity die a natural death. A slow death has something comforting about it. The dogma of Christianity gets worn away before the advances of science. Religion will have to make more and more concessions. Gradually the myths crumble. All that's left is to prove that in nature there is no frontier between the organic and the inorganic. When understanding of the universe has become widespread, when the majority of men know that the stars are not sources of light, but worlds, perhaps inhabited worlds like ours, then the Christian doctrine will be convicted of absurdity. Originally, religion was merely a prop for human communities. It was a means, not an end in itself. It's only gradually that it became transformed in this direction, with the object of maintaining the rule of the priests, who can love only to the detriment of society collectively.... Christianity, of course, has reached the peak of absurdity in this respect. And that's why one day its structure will collapse. Science has already impregnated humanity. Consequently, the more Christianity clings to its dogmas, the quicker it will decline.-Adolf Hitler, Hitler's Table Talk, pp 58-62]