The Topa soon compelled the pastoral nations of the eastern desert to acknowledge the superiority of their arms; they invaded China in a period of weakness and intestine discord; and these fortunate Tartars, adopting the laws and manners of the vanquished people, founded an Imperial dynasty, which reigned near one hundred and sixty years over the northern provinces of the monarchy.

Some generations before they ascended the throne of China, one of the Topa princes had enlisted in his cavalry a slave of the name of Moko, renowned for his valor, but who was tempted, by the fear of punishment, to desert his standard, and to range the desert at the head of a hundred followers.

This gang of robbers and outlaws swelled into a camp, a tribe, a numerous people, distinguished by the appellation of Geougen; and their hereditary chieftains, the posterity of Moko the slave, assumed their rank among the Scythian monarchs.

The youth of Toulun, the greatest of his descendants, was exercised by those misfortunes which are the school of heroes.

He bravely struggled with adversity, broke the imperious yoke of the Topa, and became the legislator of his nation, and the conqueror of Tartary.