In 1938 the Watchtower Society published the book "Crusade Against Christianity" in German. It was published in French the next year. Apparently this is one of the few books authorized by the Watchtower Society which was never published in English. It details some of the persecutions of JWs under Hitler's Third Reich. Some WT references to it:
Dec. 1, 1965 WT, p. 733
Meantime, in Germany, the Nazi fury rages and our brothers are exposed to frightful, inhuman persecution, which they withstand even at the cost of their lives. Documented material that reaches our office about such persecution is carefully preserved. Then Brother Rutherford approves publishing a book giving the evidence of the sufferings of Jehovah's witnesses in Germany. It appears under the title "Kreuzzug gegen das Christentum" ["Crusade Against Christianity"] in the German language. It is also published in French and Polish.
Dec. 1, 2004 WT, p. 26
In 1936 and 1937, the Gestapo conducted mass arrests and threw thousands of Witnesses into prisons and concentration camps, where they suffered the most cruel and sadistic treatment. The branch office in Bern, Switzerland, began gathering reports, including some that were smuggled out of the camps, for a book called Kreuzzug gegen das Christentum (Crusade Against Christianity), an exposé of Nazi crimes.
YB 80 p. 86
In 1938 Brother Franz Zürcher from Berne Bethel published a book entitled "Crusade Against Christianity," giving a detailed report on the persecution of Jehovah's Witnesses in Nazi Germany. The following year the book was published in French.
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