OK, here's the scenario: in the early thirteenth century, some Khan comes around and unites the various Turkic and Mongolic tribes. Then he conquers northern China, all of Central Asia, and parts of Iran. His successors conquer the rest of Iran and the whole middle east all the way into Asia Minor, as well as much of eastern Europe all the way into the Balkans parts of Burma and the rest of China within only two generations. They would also vassalize Korea and Vietnam during this time as well.
Plausible, or ASB?