We're in the timeline where he was stopped and had to kill himself, not sure I really want to give him any pointers about how to further his agenda but slightly differently and avoiding some tactical mistakes. I don't think he's going to take from the book that his world view was wrong or that for the good of Germany he should abandon his goals.
That book would inform him that if he starts a war to expand Germany, the actual result will be to make Germany a lot smaller, divided into a liberal and a communist state (until the communist one gets absorbed into the liberal one), and him remembered as possibly the worst person to have ever lived.
Pretty sure he'd only wonder what he did "wrong" during his years in charge, if the book doesn't dive into that detail, and try something different. He'd probably feel even more infatuated with his idea of "glorious aryan german nationalism" if the book mentions, even by passing, that the werhmacht quickly beat France into submission.
Hitler was egomaniacal I don't think he would have a change of heart, but instead use any information too alter the outcome.
But if you're going to send a book to one of the worst people in history it's gotta be one of the worst books in history. Just gotta find the right age to send him The Game: Penetrating the Secret Society of Pickup Artists by Neil Strauss. I need AI to get to the next level so I can see how this might play out.
One of my college text books on Electromagnetism with the heavy calculus and derivations of Maxwell's Equations to either Leonhard Euler or Isaac Newton, one of the extremely few people in the 17th century that would be able to understand the math and use the math to actually generate electricity.
Please reconsider avoiding Newton if you are offered the opportunity to send a book back in time. He was a narcissistic dick who used his influence to fuck over other academics (Leibniz, Hooke), and plagiarized and stole the work of others without crediting them (Flamsteed).
A science book and a noteworthy thinker. But probably not terribly far back. It's not like knowledge of electricity would go terribly far before other technologies (manufacturing, for sure) were ready to enable it to flourish.
Quite like to send the Complete Works of William Shakespeare back to the guy himself. Seeing he's already written it that would free him up to write a whole bunch more.
Would be cool to do the same thing with certain scientists.
I like to imagine giving a big World Atlas of some sort to any seafaring culture around 500AD would result in interesting consequences, possibly with it becoming a real treasure. Maps are like pictures and valuable even if the places' names can't be understood
Have it printed on a series of cave walls that go deep into the ocean and by the time the present comes around again, maybe we'll have fully explored the oceans and there will still be unexplored land.
I'd like to prevent many tragedies, but I'm not sure a single book would change history. I can actually imagine it going very wrong...
— Mein Führer, this book here explains our theories about the origin of the German population and about the natural maliciousness of Jews are wrong.
— Let me see... Lies, all lies! This here is evidence of their pervasive propaganda against the aryan people.
— Witchfinder General, a book had arrived... from the unknown.
— What kind of sorcery is this? "Witches do not exist". "...These trials were the result of ignorance and greed". What in the name of God is this blasphemy? A powerful witch is near and these are her evil tricks!
A book on how to make weapons or improve trade, so that people will try it out.
But after the first 3 items or so(to show that the book is legit) we shift to stuff that accelerates science very much.
Get them to create electricity and radio waves earlier.
Society gets to progress faster.
Tho, who should it be sent to? Someone religious? In that case it'd be better to mask it as a religious text, where god is revealing the workings of the universe and encouraging humans to find out more about his design by observation and experimentation?