Probably at no period during its long history has the Chinese empire been subjected to such a thorough shaking up, to such a complete upsetting and reversal of its ancient ways, as during the advance of the Mongols from the north to the south during the twelfth and thirteenth centuries. When they had at length subdued the whole land, there was a moment during the rule of the liberal-minded Kublai Khan when the old barriers and prejudices seemed to have been broken down, and when the Middle Kingdom appeared to be about to enter the general comity of nations. This is what gives to Marco Polo’s account of the country, which he visited at the time, so very ‘un-Chinese’ an air. We hear of Italian friars and French goldsmiths at the court, and of projected embassies from the Pope. Still closer were the relations with the Mohammedan people of Western Asia, then ruled by members of Kublai’s family. Marco Polo, we know, formed part of the escort of Kublai’s sister, when she travelled by sea to Persia to become the bride of the Mongol khan of that country; and a predecessor of this latter ruler, Hulugu, as early as the middle of the thirteenth century, brought over, it is said, as many as a thousand Chinese artificers and settled them in Persia. And yet when scarcely two generations later the degenerate descendants of Kublai were driven from the imperial throne and replaced by a native dynasty, what slight permanent trace do we see of all these changes reflected in the arts of the Middle Kingdom! No doubt, on looking closely, we should find that a change had taken place during these years: new materials had been brought in, new forms and new decorations applied to the metal ware and the pottery of the Chinese. It is in connection with these two arts especially (and we may add to them the designs on textile fabrics) that we find so many points of interest in the mutual influence of the civilisations of China and Persia at this time. We must remember that in the thirteenth century the craftsman of Persia, as the inheritor of both Saracenic and older traditions, was in many respects ahead of his rival artist in China. As far as the potter’s art was concerned this was the first meeting of two contrasted schools, which between them cover pretty well the whole field of ceramics--of that part at least of the field in which the glaze is the principal element in the decoration.[35]