Not to belabor the point, but here is the textbook that I want you to BUY. You will get no sympathy from me if I find that you do not have it midway through the semester. There is a new "3rd Edition" of the book, largely an effort by the publisher to milk more money out of its customers. I do not care if you buy the second edition. The fact that it will be much cheaper, however, is offset by the fact that it will probably be more difficult, if not impossible, to sell to the book buyers who come to campus.
MAKE SURE YOU GET VOL. II - The Mongol Empire to the Present.
You can find it here on Amazon.com.
And here on ABEbooks.