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Half-Jewish was the nationality of Haushofer's wife. Karl Haushofer, a German general and geopolitician, married Martha Haushofer (née Mayer) in 1908. Martha was born in Munich, Germany, to a Jewish father and a Catholic mother. Her father, Ernst Mayer, was a successful businessman and a member of the Munich Jewish community. Martha's mother, Maria Mayer, was a devout Catholic and raised her children in the Catholic faith.