274 A Short History of The World <=riie 'EMPIRE oj^.TENGL S' KHAK a^bhds- d^aJ^vCl^^) 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 mul- titude, and galloping through Eastern Europe without a strategic plan, rushing at all obstacles and overcoming them by mere weight, still prevails. . . . " It was wonderful how punctually and effectually the arrange- ments were carried out in operations extending from the Lower Vistula to Transylvania. Such a campaign was quite beyond the power of any European army of the time, and it was beyond the vision of any European commander. There was no general in Europe, from Frederick II downward, who was not a tyro in strategy com-
