Not a quick read, this book will probably tell you lots more than you wanted to know if you have just a casual interest in the subject. That aside, it covers its subject thoroughly. Analyzing word etymology, documents, and institutions, Halperin shows that the Russians borrowed quite a bit from the Mongols -- and that the 300-year "Tatar Yoke" was far from being a dark age for Russia. One thing that particularly grabbed me: Halperin indicates that pre-conquest Russian scribes attributed nomad raids to punishments from God. So, how did the scribes handle the situation after the conquest, when Christians were under the domination of infidels? By denying the conquest had occurred!