used in small field guns. He completed the conquest of the Kin Empire and then swept his hosts right across Asia to Russia (1235), an altogether amazing march. Kieff was destroyed in 1240, and nearly all Russia became tributary to the Mongols. Poland was ravaged, and a mixed army of Poles and Germans was annihilated at the battle of Liegnitz in Lower Silesia in 1241. The Emperor Frederick II does not seem to have made any great efforts to stay the advancing tide.
“It is only recently,” says Bury in his notes to Gibbon’s Decline and Fall of the Roman Empire, “that European history has begun to understand that the successes of the Mongol army which overran Poland and occupied Hungary in the spring of A.D. 1241 were won by consummate strategy and were not due to a mere overwhelming superiority of numbers. But this fact has not yet become a matter of common knowledge; the vulgar opinion which represents the Tartars as a wild horde carrying all before them solely by their multitude, and galloping through Eastern Europe without a strategic plan, rushing at all obstacles and overcoming them by mere weight, still prevails. . . .