Thea von Harbou [who would become Fritz Lang's second wife] was blond and blue-eyed, a stately German type... Her lineage was more Prussian than Lang's monocle.... Educated in a convent and by private tutors... Like Lang, von Harbou also enjoyed popular fiction; she worshiped Karl May and in her twenties could regale visitors by reciting May's translation of parts of the Koran.McGilligan, page 64:
Von Harbou [Fritz Lang's girlfriend and wife-to-be] was, like Lang, fascinated with India... Her first scenario in collaboration with Lang would exploit their mutual fixation with India... Von Harbou was busy with the adaptation of her 1917 novel Das indische Grabmal (The Indian Tomb), when Joy May assigned Lang to help her with the writing and plan the details of production. Her novel was about a German architect who falls in love with a temple dancer in India. The scenario would be divided... into two parts: Part One, called Die Sendung des Yoghi (The Mission of the Yogi), would be followed by Part Two, Das indisch Grabmal.McGilligan, pages 87-88:
At the same time, von Harbou and Lang began to develop a second project, an original story that could not have been more dissimilar from the Indian epic. This scenario was drenched in melodrama and Christian mythology. The plot involved a woman and an out-of-wedlock child fathered by an author-philosopher who espouses free love. The illegitimate mother marries the man's twin brother. The author fakes his own suicide and goes off to live as a hermit in the mountains, where he is pursued by the distraught woman. The story ends with a miracle amid a spectacular snowstorm and avalanche, with a statue of the Virgin Mary that appears to come alive and walk on the snow. Hence the working title: "Madonna im Schnee."
May... gave a priority go-ahead to Das wandernde Bild (The Wandering Image), as "Madonna im Schnee" was eventually retitled. [More about the making of this film, one of many made by Lang that featured overt Catholic themes and imagery.]
The period of hard work, the crisis of his [Fritz Lang's first] wife's death, the presures of making Doktor Mabuse, der Spieler--all had passed by the mid-summer of 1922. Perhaps, then, it was merely to keep up appearances that Fritz Lang and Thea von Harboou decided to be married, on August 26, 1922, in Berlin-Schmargendorf at 8:30 A.M. They formally celebrated the success of the film, and cemented their husband-and-wife partnership.McGilligan, pages 169-170:
In the marriage papers, Lang, following his father's example, declared his religion as agnostic ("without confession"), while von Harbou named herself a Protestant. Shortly after the wedding, according to her World War II interrogation papers, she stopped practicing any religion, "for private reasons."
Adolf Hitler became chancellor of Germany on January 30... Many artists and intellectuals left Berlin immediately following the Reichstag fire, which Hitler blamed on the Communists, and which the Nazis used to whip up public furor... Lang himself rarely mentioned his mother's [Jewish] background; when he did, it was a circumstance he played down, or misstated, or--in the most generous interpretation--regarded as irrelevant for most of the first half of his life, until history decreed otherwise. He steadfastly referred to himself as Catholic, though, ironically, many people in Germany's film world took it for granted that the director of Metropolis and M was Jewish.McGilligan, page 181:
With the rise of the Nazis and their hate-filled propaganda, anti-Semites--often with more than one ax to grind--made it their duty to ferret out ancestral clues and pigeonhole people as Jewish. And Fritz Lang had already begun to be mentioned within that category. The French magazine Cinemonde, for one, had referred to Lang as a Jew in its December 19, 1929, issue. "Although Jewish," reported the magazine, discussing the pros and cons of the director's latest motion picture, Die Frau im Mond, "Lang possesses all the qualities and faults of the Germanic race: patience, scientific application, reasonable temerity, but also grandiloquence, bombast, pride, chauvinism."
Lang would not have missed such an indiscreet item, and he would hvae to worry about its resonance in an increasingly Nazified Germany. There may have been similar squibs locally in Berlin. Several people interviewed for this book mentioned a rumor that they remembered circulating in Berlin early in 1933, a revelation, much bruited about in film circles, which alleged as fact what many of them already presumed--that Fritz Lang, the leading director in all of Hitler's Germany, was a Jew. "Some malicious tongue came out with the story that Mr. Lang's grandmother on one side or another was Jewish, and he fell out of favor," remembered Harold Nebenzal.
Some attributed this rumor to Thea von Harbou, Lang's estranged, Nazi-leaning wife--she who knew the family history. To whatever extent von Harbou was a Nazi, however, there is no hint of her acting spitefully toward Lang, nor any record of anti-Semitic words or deeds on her part...
March and April  were certainly hectic months: the banning of Das Testament, Goebbels in public and private... and the dissolution of the marriage between Fritz Lang and Thea von Harbou... The divorce rocked Berlin's film scene. Even in America the news was reported in the press, giving as one of the causes of their separation the revalation that Fritz Lang was "not Aryan."McGilligan, pages 183-184:
By 1938... Fritz Lang's disertion of Germany in favor of the United States. By then, the director had made it clear that he would never return to the fatherland. He had been stripped of German nationality and had taken the U.S. pledge of citizenship, and he was conspicuously engaged in directing highly-touted movies in Hollywood, wher he was widely reported by the press asa virulent anti-fascist opposed to Hitler's dictatorial regime.More about Fritz Lang's second wife, Thea von Harbou, from: McGilligan, pages 330-331:
Even so, over time Lang was spared the worst of the Nazi vilification suffered by Jewish and non-Jewish artists who chose to leave Germany. There seems to hve been genuine regret in his case, as if the Nazi leaders also blamed themselves for fatally misreading the man who had directed their immortal Die Nibelungen...
Lang, however, was included indirectly in Fritz Hippler's 1940 pseudo-documentary Der ewige Jude (The Eternal Jew) which included scenes from M in it ssweeping attack on "degenerate Jewish art." Hans Beckert's final monologue, inserted out of context, was presented as a Jewish confession, proving the race was incapable of controlling its base desires and unfit to live in a "moral society." One of the most memorable soliloquies in cinema, the final monologue was ironically the speech for which Fritz Lang always gave undiluted credit to his wife and collaborator Thea von Harbou, who was in fact in solid standing with the Nazis.
All famous people who had joined the NSDAP [National Socialist German Workers' Party, i.e., the Nazis] were suspect in Germany after the war [World War II], and Thea von Harbou was detained in Staumuhle, a pison camp run by the British, from July 10 through October 10, 1945...
Whether von Harbou or her interrogators jotted down the comment in her detention papers that she was divorced from "the Jewish director Fritz Lang" is uncertain, but otherwise her former husband did not come up in the questioning. Von Harbou denied any anti-Semitism, denied involvement in any Aryanization of Jewish property, noting instead several instances where she had acted as a good Samaritan--helping people out of Germany or out of trouble with Goebbels (including her Jewish secretary Hilde Guttmann and actor Alfred Abel, who had played the master of Metropolis). "Although I am unwilling to mention things that I once found a matter of course," von Harbou told the interrogators, "I don't think there is anyone who can claim that I hurt or insulted them because of their race."
It is sadly true, however, that she prospered during the Nazi reign. Von Harbou worked with dedicated Nazi filmmakers such as Gustav Ucicky and Veidt Harlan, the latter the director of the infamous Jud Suss (1940)--a film described by historian Richard Grunberger as "the cinematic curtain-raiser for the Final Solution." She seemed at the beck and call of that Staatsrat, or "Artist of the State," actor Emil Jannings, one of the most prominent Nazi enthusiasts, and a friend from the time of her salad days in the theater. Von Harbou acted as a "script doctor" or consultant on several Jannings vehicles. And she wrote the script for at least one film (1943's Die Gattin) starring one of Goebbels's actress-girlfriends, Jenny Jugo.
Her annual income, which she listed for the American questionnaire ranged near 120,000 Reichsmarks a year, or close to the tremendous sum of $50,000. The spring of 1940, when she admitted to joining the [Nazi] party, was actually a propitious time to become a Nazi: Things were going well in the war, and it might not have seemed like any kind of risk.
Significantly, even in the formal statement she made in her own defense, von Harbou didn't distance herself from the Nazi ideology, nor express any repentance for Third Reich wrongdoing. This was something that always bothered even some of her close relatives. Her nephew, Vinayak Tendulkar, lived with her as a boy for almost a year after the war. "She never criticized in any way," said Tendulkar, "never mentioned any dislike of the Nazis. She must have known, because she was moving in Germany's high society, of the inhuman rule of the Nazis--the treatment of Jews and others."
Von Harbou's indomitable, upbeat personality did not change. In prison she directed a version of Faust. Once released, the scenarist of Der mude Tod, Die Nibelungen, Metropolis, and M toiled as one of the Trummerfrauen, or "rubble women," for a solid year, from October 1945 to October 1946. To earn her food rations and coupons, she stooped among the rubble, separating the good bricks from bad, helping to rebuild Germany.
People in Hollywood remembered [Fritz] Lang cackling when he learned von Harbou had been reduced to collecting bricks from Berlin rubble. Yet her interrogation papers point out that, at age fifty-seven, she would have been exempt from this back-breaking work: Von Harbou had volunteered.