We had a discussion on this issue before and traced the story back to original German cites from during the war. Somebody really did mistakenly translate Casablanca as White House and the Germans really did think Roosevelt and Churchill were meeting in Washington.
One reason that the Germans studied the languages of Native Americans in the period between World War I and World War II is that modern linguistics was invented by academics in Germany and the nearby countries of Europe around that time. Modern linguistics began with the publication in 1916 of the book Cours de linguistique générale (Course in General Linguistics) by the Swiss linguist Ferdinand de Saussure. Before then there was some study of the history of particular languages. However, linguists didn’t spend much time trying to understand the structure of languages with little contact with European people. They didn’t try to understand the languages of North American, South American, African, Asian, Australian, New Zealander, and Pacific Islander countries. Often they would colonize those countries and try to eliminate the speaking of the native languages of those places by their own people.
They believed that Latin and Greek were the ideal languages and modern European languages were close to it. They didn’t really understand how to understand the structures of other languages. In the early twentieth century they finally began trying to understand the native languages of other peoples of the world. They began to realize that their structures were vastly different. They began to understand the vast numbers of structures that existed in the vast number (perhaps about 7,000) of languages in the world.
Another, more trivial, reason was that westerns were surprisingly popular in Germany. German authors like Karl May, Friedrich Gerstacker, and Balduin Mollhausen wrote popular adventure novels centered around American Indians. Hitler, among others, was a fan.
This is quite off-topic now, but it seems most of the thread has left the OP behind….
I’m not convinced by those posts. There are two supposed sources:
The first is an indirect citation of the book “Roosevelt and Churchill : men of secrets” by David Stafford which contains this claim of mistranslation but doesn’t give a source for it.
The second are the diaries of Joseph Goebbels, who does indeed complain on the 28th of January 1943 that the “Nachrichtendienst” was unable to ascertain the place of this meeting beforehand, and states that it had been expected to take place in Washington. However, he crucially does not mention the White House or an error in translation. Given that he writes voluminously and twice in that entry abuses the Nachrichtendienst for being expensive and useless, I think he would have mentioned it.
To me, it seems much more likely that Washington / the White House is an obvious, logical place for such a meeting and someone later confabulated a translation error to match the trope of the stupid Nazis.