The third possibility is that Adolf Hitler's grandfather was Jewish. Rumours to that effect circulated in Munich cafes in the early 1920s, and were fostered by sensationalist journalism of the foreign press during the 1930s. It was suggested that the name Huttler' was Jewish,revealed' that he could be traced to a Jewish family called Hitler in Bucharest, and even claimed that his father had been sired by Baron Rothschild, in whose house in Vienna his grandmother had allegedly spent some time as a servant. But the most serious speculation about Hitler's supposed Jewish background has occurred since the Second World War, and is directly traceable to the memoirs of the leading Nazi lawyer and Governor General of Poland, Hans Frank, dictated in his Nuremberg cell while awaiting the hangman.
http:// www.nytimes.com/books/first/k/kershaw-hitler.html