As I stated earlier, Wind from the East focuses on the Mongols, but also allows for other easterners, namely the Kuei-Jin and a werewolf tribe called the Stargazers, to be added into your stories. It also gives you some insight into what the east was like in the Dark Ages and allows for whole chronicles there. This book is great and keeps White Wolf's tradition of awesome Sourcebooks going.
The next chapter covers things from a vampiric perspective. A brief overview is given of all the Cainite clans (and some bloodlines) and how they react to the Mongols. Some clans, like the Assamites in Khwarazm and the Tzimisce in Russia find their territories threatened by the Mongol horde. Others, like Gangrel and Ravnos, find wandering with the Horde to be to their liking. Next we are given some notes on two other bloodlines exclusive to the Mongol empire. One is the Anda, a bloodline of Mongol and Central Asian Gangrel that has wandered the Steppe for milennia. The other, the Wu Zao, are forgotten Salubri that Salout abandonned in Asia.
Also in this Chapter are details on the Kuei-jin. The Kindred of the East have long claimed all of Asia as their domain and do not take kindly to outsiders, like the Anda, in their midst. This section covers the traditions and beliefs of the Black Tortoise Court, including some prominent corpse families and their interesting relations with the Hengeyokai and spirits of the earth. Following this is a chapter on mechanics and other juicy stuff. Some unique Animalism powers are given for the Anda, and some unique Mongol rites are given for the Black Tortoise Court. Also given are some new Merits and Flaws and a new path, focusing on Mongol concepts of honor and warfare. Some information is also given for combat and the like as well.
The book closes out with some pre-made characters, some of which are quite interesting like the yam courier and the wise woman. Some sample NPCs are given in the back as well. However, there is a definate focus on Cainites over Kuei-jin here.
All in all, this is an excellent source book for including Mongol characters. Enough stuff is given where you could even use this for playing other supernaturals like Mongol Dreamspeakers, Sons of Tengri, Hengeyokai, Shadow Lords, hsien, Eshu and who knows what else. The possibilities are really endless. If you want a historical game with Mongols, you really should get this book.