What evidence is there to show conclusively that Hitler was or was not Jewish or had Jewish ancestry even if he was not a practicing Jew?
It's not known with full certainty who Hitler's father's father was (although George Hiedler is the generally accepted one). For a list of theories on the matter, see the Wikipedia article about Alois Hitler.
Since Hitler's father's mother got pregnant while allegedly working for a Jewish family it has been claimed that the father is actually the 19-year old son of this Jewish family. That would make Adolf Hitler one quarter Jewish according to the race laws in Nazi Germany.
However, there is not a smidgen of evidence for this theory. It has become popular because of the immense potential for irony, should it be true. But it probably isn't.
Source: Frank McDonough, Hitler and the rise of the Nazi Party, Pearson Education, 2003, p. 20.
5It has become popular because of the immense potential for irony, should it be true. -- I think it has become popular because it pins the holocaust on the Jews. Apr 23, 2011 at 18:48
14But even if it was true, that would not pin the Holocaust on the Jews. Hitler would likely have been unaware of his Jewish heritage, and not even seen as a Jew in the matrilinear traditional view. And one person is not "the Jews". So that makes absolutely no sense whatsoever in three different ways. Apr 23, 2011 at 20:04
4@Lennart, I am not sure you understand how anti-semitism, or bigotry or racism for that matters works. Making logical sense is the least of it. The question remains, if it is clear that Hitler was not Jewish, why is this meme so popular? None of the answers here address that. My suggestion is that the question allows antisemites to absolve Germany of the Holocaust and pin it on the Jews, much like the Jews and Judas were blamed for killing Christ, a Jew. It's another example of Jewish evil. Even Hitler was Jewish. Here is a book at Amazon - read just the description: amzn.to/kTyk8S Apr 28, 2011 at 19:33
4@Jerry: No, that question does not remain, it has been answered. It's so popular because if it was true, it would be the biggest "ooh isn't that ironic" of humankind. Your answer is assuming that anyone going "Hitler was part Jewish" is stupid and anti-semitic. But those who want an excuse for the holocaust goes a much easier way: Denying it ever happened. That means there is nothing to pin on anyone. But pinning it on Jews via a Jewish Hitler means you must admit it happened. And then the Jewish evil is turned...against Jews? That doesn't fit with the conspiracy. So no. Doens't work. Apr 28, 2011 at 20:22
5@jwenting No, that was certainly not the case with the German Race laws. Racism in general, and Nazism in particular is based on the idea that mixing races "defiles" the blood. If it's a mother or a father makes no difference. en.wikipedia.org/wiki/Mischling_Test Jul 15, 2013 at 6:04
Who is a Jew?
The definition of who is a Jew varies according to whether it is being considered by Jews based on normative religious statutes, self-identification, or by non-Jews for other reasons. Because Jewish identity can include characteristics of an ethnicity, a religion, and citizenship, the definition of who is a Jew has varied, depending on whether a religious, sociological, or ethnic aspect was being considered.
Genome-wise: He surely shared genome with the Jewish population. We all come from a common ancestor. Furthermore, there is no such thing as a Jewish race, so the question does not make much sense when seen from this point of view. Everybody is related to Jews.
Religion-wise: He had a Christian family and education:
Nationality-wise: He was Austrian first, and then German. There is no evidence or historical doubt that his nationality was other then Austrian/German.
Self-identification-wise: He didn't really like Jews, so I doubt he self-defined as one:
"If I am ever really in power, the destruction of the Jews will be my first and most important job. As soon as I have power, I shall have gallows after gallows erected, for example, in Munich on the Marienplatz-as many of them as traffic allows. Then the Jews will be hanged one after another, and they will stay hanging until they stink. They will stay hanging as long as hygienically possible. As soon as they are untied, then the next group will follow and that will continue until the last Jew in Munich is exterminated. Exactly the same procedure will be followed in other cities until Germany is cleansed of the last Jew!"
According to Nazi laws: unlikely (but the laws seem recursive to me, so it's really hard to say). I doubt that any German tribunal would have declared him a Jew in those times. For more information see Wikipedia.
16The baptism certificate can be seen here. But it must be fake - everyone knows Hitler was born in Kenya! :) Apr 23, 2011 at 12:24
6I'm not trying to stalk the diamond mods, but I don't think this is a good answer. For "genome-wise", you state we all share a common ancestor, but you don't provide any evidence that the last common ancestor was Jewish. For "Nationality-wise", you don't expand upon the brief mention of nationality and Jewishness in the introductory paragraph, and how being Austrian or German is relevant. Apr 23, 2011 at 12:42
4Chimpanzees and human beings "all come from a common ancestor." So do whales and hippopotamuses. Does this mean it is impossible to distinguish between a chimpanzee and a human being, or a whale and a hippo, to say they have no genetic differences? I don't know if Ashkenazi Jews can be properly called a "race", since obscurantists have twisted that word to require a strenuous level of difference, but A. Jews are certainly inbred to a point that no geneticist would confuse them with a European -- they have a long-lived Semitic DNA signature, they are certainly a population unto themselves. Apr 23, 2011 at 14:16
2So -1 for empty cliches. Apr 23, 2011 at 14:16
3@Sklivvz Ashkenazi Jews, "European" Jews, are obviously the only sub-population of Jews relevant to this question. Are you arguing otherwise? And my point makes perfect sense. Consider a population characterized by DNA made of 6-digit binary string, with each bit having equal probability of being 0 or 1; 001000 and 101010 would be members. In a large, randomly mating population, the progeny of one mating of individuals differs from every another mating of individuals in an average 3 places, the same as the average genetic distance between their parents -- that is the definition of random. Apr 23, 2011 at 15:37
was Jewish. And how would somebody prove his ancestries 3000 to 4000 years back? And even if you could find a grandfather - what would it show? The question is only relevant for racists. To be a Jew is a religion, and there is no Jewish gen, nor a Jewish nation.