Genghis Khan's Greatest General: Subotai the Valiant - Richard A. Gabriel Not a bad read. The problem with the biographies of people living 800 years ago (or a similarly remote period) is that there's usually not a lot of primary sources to evaluate. If you're lucky you have a couple of histories; if you're really lucky you have a few letters & inscriptions or similar material; if you're really, really lucky you have something actually written by the subject.

Beyond that it's all speculation and inference.

With the material we've got, the author did a good job. I guess my real "beef" is a philosophical one: I have a guilty admiration for the military commander who's more than just a soldier (like Scipio Africanus or Napoleon) but, in the end, these men's primary job was destroying other people's lives, oftentimes with no defensible justification, hence the "guilt."

Mongol historical revisionism may laud some of the effects of their conquests (like reopening the overland trade routes through Asia) but I think, in the end, the original assessment that they were the "scourge of God" is closer to their real impact than otherwise.