Khokand, Bokhara fell and then Samarkand, the capital of the Kharismian empire. Thereafter nothing held the Mongols in the Kharismian territories. They swept westward to the Caspian, and southward as far as Lahore. To the north of the Caspian a Mongol army encountered a Russian force from Kieff. There was a series of battles, in which the Russian armies were finally defeated and the Grand Duke of Kieff taken prisoner. So it was the Mongols appeared on the northern shores of the Black Sea. A panic swept Constantinople, which set itself to reconstruct its fortifications. Meanwhile other armies were engaged in the conquest of the empire of the Hsia in China. This was annexed, and only the southern part of the Kin empire remained unsubdued. In 1227 Jengis Khan died in the midst of a career of triumph. His empire reached already from the Pacific to the Dnieper. And it was an empire still vigorously expanding.
Like all the empires founded by nomads, it was, to begin with, purely a military and administrative empire, a framework rather than a rule. It centred on the personality of the monarch, and its relations with the mass of the populations over which it ruled was simply one of taxation for the maintenance of the horde. But Jengis Khan had called to his aid a very able and experienced administrator of the Kin empire, who was learned in all the traditions and science of the Chinese. This statesman, Yeliu Chutsai, was able to carry on the affairs of the Mongols long after the death of Jengis Khan, and there can be little doubt that he is one of the great political heroes of history. He tempered the barbaric ferocity of his masters, and saved innumerable cities and works of art from destruction. He collected archives and inscriptions, and when he was accused of corruption, his sole wealth was found to consist of documents and a few musical instruments. To him perhaps quite as much as to Jengis is the efficiency of the Mongol military machine to be ascribed. Under Jengis, we may note further, we find the completest religious toleration established across the entire breadth of Asia.
At the death of Jengis the capital of the new empire was still in the great barbaric town of Karakorum in Mongolia. There an assembly of Mongol leaders elected Ogdai Khan, the son of Jengis, as his successor. The war against the vestiges of the Kin empire
