Mistislaf had probably no objection to the Poloftsi being annihilated by some tribe stronger and fiercer than themselves, for they gave him a great deal of trouble by their frequent raids; but he perceived the force of the argument about his own turn coming next, and thought it wise to assist his usually hostile neighbours. For the purpose of warding off the danger he called together the neighbouring Princes, and urged them to join him in an expedition against the new enemy. The expedition was undertaken, and ended in disaster. On the Kalka, a small river falling into the Sea of Azof, the Russian host met the invaders, and was completely routed. The country was thereby opened to the victors, but they did not follow up their advantage. After advancing for some distance they suddenly wheeled round and disappeared.
Thus ended unexpectedly the first visit of these unwelcome strangers. Thirteen years afterwards they returned, and were not so easily got rid of. An enormous horde crossed the River Ural and advanced into the heart of the country, pillaging, burning, devastating, and murdering. Nowhere did they meet with serious resistance. The Princes made no attempt to combine against the common enemy. Nearly all the principal towns were laid in ashes, and the inhabitants were killed or carried off as slaves. Having conquered Russia, they advanced westward, and threw all Europe into alarm. The panic reached even England, and interrupted, it is said, for a time the herring fishing on the coast. Western Europe, however, escaped their ravages. After visiting Poland, Hungary, Bulgaria, Servia, and Dalmatia, they retreated to the Lower Volga, and the Russian Princes were summoned thither to do homage to the victorious Khan.
At first the Russians had only very vague notions as to who this terrible enemy was. The old chronicler remarks briefly: "For our sins unknown peoples have appeared. No one knows who they are or whence they have come, or to what race and faith they belong. They are commonly called Tartars, but some call them Tauermen, and others Petchenegs. Who they really are is known only to God, and perhaps to wise men deeply read in books." Some of these "wise men deeply read in books" supposed them to be the idolatrous Moabites who had in Old Testament times harassed God's chosen people, whilst others thought that they must be the descendants of the men whom Gideon had driven out, of whom a revered saint had prophesied that they would come in the latter days and conquer the whole earth, from the East even unto the Euphrates, and from the Tigris even unto the Black Sea.
We are now happily in a position to dispense with such vague ethnographical speculations. From the accounts of several European travellers who visited Tartary about that time, and from the writings of various Oriental historians, we know a great deal about these barbarians who conquered Russia and frightened the Western nations.
The vast region lying to the east of Russia, from the basin of the Volga to the shores of the Pacific Ocean, was inhabited then, as it is still, by numerous Tartar and Mongol tribes. These two terms are often regarded as identical and interchangeable, but they ought, I think, to be distinguished. From the ethnographic, the linguistic, and the religious point of view they differ widely from each other. The Kazan Tartars, the Bashkirs, the Kirghiz, in a word, all the tribes in the country stretching latitudinally from the Volga to Kashgar, and longitudinally from the Persian frontier, the Hindu Kush and the Northern Himalaya, to a line drawn east and west through the middle of Siberia, belong to the Tartar group; whereas those further eastward, occupying Mongolia and Manchuria, are Mongol in the stricter sense of the term.