During Hitler's nine-month imprisonment for trying to overthrow the German government in 1923, he wrote the book that would become the basis of his fortune — "Mein Kampf," or "My Struggle."
Initially sales of Hitler's anti-Semitic diatribe didn't capture Germany's attention.
"They sold, so-so," Dr. Pascal Trees, a research associate at the Institute for Contemporary History, said in the Smithsonian documentary "Hitler's Riches."
"To be perfectly frank, it's not a good read," Trees said.
The führer's notorious memoir was first published in 1924 and cost 12 deutsche marks, according to Trees.
To spur sales, the Nazis decided to produce a newer, more straightforward edition of the manifesto.
The Third Reich, however, was still searching for a way to get Hitler's book into every German home.
The opportunity to further monetize "Mein Kampf" became apparent when Hitler was elected chancellor in 1933.
"Of course there were a lot of marriages, there always are, and then they all had to be paid for by the state," author of "Hitler's Fortune" Dr. Cris Whetton said in "Hitler's Riches."
"The state bought the books [Mein Kampf] to present to every married couple, and Hitler reaped the profits," Whetton added.
At the time, Hitler earned a 10% royalty from every sale of the book that became the official state wedding present to newlyweds.
At the peak of "Mein Kampf" sales, Hitler earned $1 million a year in royalties alone, equivalent to $12 million today.
By 1939, Hitler's work had been translated into 11 languages with 5,200,000 copies sold around the world.
What's more, since Hitler was chancellor of Germany, he was exempt from the 400,000 deutsche marks (approximately $120,000 in today's dollars) he owed in taxes, according to "Hitler's Riches."
"The authorities presumably with a little bit of pressure said we think it's reasonable as chancellor Herr Hitler should not paid tax," Whetton said.
Since the end of World War II, the Führer's manifesto has not been reprinted because the rights have been held for 70 years by the state of Bavaria, which has refused to allow reprints.
Now that the copyright has expired, the first copies of an annotated edition of Hitler's 'Mein Kampf' from Munich's Institute of Contemporary History went on sale for $64 on Friday, the Associated Press reported.
The 2,000-page edition will be accompanied with more than 3,500 academic notes.
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