A European army necessarily diminishes in force and its existence becomes more and more imperilled as it advances from its base of operations into a foreign and hostile country.  Not so a horde like that of Genghis Khan in a country such as that which it had to traverse.  It needed no base of operations, for it took with it its flocks, its tents, and all its worldly goods.  Properly speaking, it was not an army at all, but rather a people in movement.  The grassy Steppes fed the flocks, and the flocks fed the warriors; and with such a simple commissariat system there was no necessity for keeping up communications with the point of departure.  Instead of diminishing in numbers, the horde constantly increased as it moved forwards.  The nomadic tribes which it encountered on its way, composed of men who found a home wherever they found pasture and drinking-water, required little persuasion to make them join the onward movement.  By means of this terrible instrument of conquest Genghis succeeded in creating a colossal Empire, stretching from the Carpathians to the eastern shores of Asia, and from the Arctic Ocean to the Himalayas.

Genghis was no mere ruthless destroyer; he was at the same time one of the greatest administrators the world has ever seen.  But his administrative genius could not work miracles.  His vast Empire, founded on conquest and composed of the most heterogeneous elements, had no principle of organic life in it, and could not possibly be long-lived.  It had been created by him, and it perished with him.  For some time after his death the dignity of Grand Khan was held by some one of his descendants, and the centralised administration was nominally preserved; but the local rulers rapidly emancipated themselves from the central authority, and within half a century after the death of its founder the great Mongol Empire was little more than “a geographical expression.”

With the dismemberment of the short-lived Empire the danger for Eastern Europe was by no means at an end.  The independent hordes were scarcely less formidable than the Empire itself.  A grandson of Genghis formed on the Russian frontier a new State, commonly known as Kiptchak, or the Golden Horde, and built a capital called Serai, on one of the arms of the Lower Volga.  This capital, which has since so completely disappeared that there is some doubt as to its site, is described by Ibn Batuta, who visited it in the fifteenth century, as a very great, populous, and beautiful city, possessing many mosques, fine market-places, and broad streets, in which were to be seen merchants from Babylon, Egypt, Syria, and other countries.  Here lived the Khans of the Golden Horde, who kept Russia in subjection for two centuries.