The book takes a friendlier approach to the Mongol empire than you'd normally get from Western historians. Many of the reviews claim that it's "revisionist". It certainly depicts Genghis Khan as one of history's great men rather than a bloodthirsty tyrant and leader of pillaging hordes. On the other hand, it seems to tie together parts of Asian history that wouldn't make sense if the Mongols were just conquerers.
So, how big of a grain of salt do I need?
Edit: Link to book at Amazon
My desire for grains of salt increases looking at the "people also bought" section.
/u/rakony touched on the main points in his post below. I'm by no means an expert on mongol history, but I know enough to recognize where Weatherford seems to gloss over history.
So for context in answering this question, I think it's import to recognize the historiography involving the Mongols. For most of (Western) historical thought, the Mongols fit the "savage bloodthirsty conquerors" who raped and pillaged and nearly dragged the world into a second dark age. At some point when economic history became more popular, the Mongols were looked at again and were seen as great. They created an easy an safe trading route that could lead to the spread of new ideas (I remember reading a historian that partly credited the enlightenment to the Mongols). This, combined with the the "religious freedom" of the Empire, created a convenient narrative that portrayed the mongols as a more advanced people than the Western powers. As such, the historiographies argue back and forth with each other. The "classic" one says "the modern one overlooks the death and destruction caused by the mongols and discounts all the death and devastation they caused." The modern one fires back "Alexander and Rome did the exact same things, and they don't receive nearly the same criticism. Why are the Mongols (who arguably did more in establishing the benefits of Empire) treated differently?"
Which brings me to the actual book. I don't want to call Weatherford a revisionist, because the things he says are factually correct (as far as I can tell anyways). But the important thing is what he doesn't say. Weatherford largely glosses over the devastation and death caused by the Mongols in order to stress the good they did.
Whether you believe Weatherford comes down to one's own interpretation of history. Do you believe History should focus on the macro effects of something regardless of the consequences? Or do you believe that the human experience should be prioritized over the unintentional benefits that came later? (Ghengis wasn't out to build a peaceful trading empire, he was out to conquer).
I personally side with the latter, taking the human experiences out of history, in my opinion, dehumanizes the people that suffered through the events and creates a very problematic cost benefit model. The quote by tacitus about creating a wasteland and calling it peace always sticks with me. The "modern" interpretation is right in that we need to re-evaluate other great historical figures to the same standard as the Mongols (Alexander is a prime example in my opinion). But that shouldn't take away from the criticism of the Mongols.
Is there any ebook copy available?