So far we have been concerned almost exclusively with those portions of the Asiatic army and the hordes which followed it which came westward to the south of the Black Sea. But it must be noted that the body of invaders of the same race who had come westward to the north of that sea, and who had attacked Russia, Poland, and Hungary, had constantly received additions to their numbers. This northern division was possibly more numerous than the Turks in Asia Minor. As early as 1265, a certain Timour, the ruler of Tartars who were in occupation of territory on the Volga, had sent twenty thousand men to aid the Bulgarians against the Empire. Bulgarians and Tartars together had occupied all the passes into Thrace, and the emperor had saved himself with difficulty. In 1284, ten thousand Tartars came southward into Thrace from the great host which were in Hungary. In 1300, the Turks who had entered the Crimea were driven out by another horde of Tartars who had occupied South Russia. The number and strength of these invaders continued constantly to increase. Their power indeed remained firmly established in South Russia until long after the conquest of Constantinople. They had no special sympathy with the Ottoman Turks, and were ready, as were the Alans, to fight either for the emperor or against him. Cantacuzenus mentions that in 1324 one hundred and twenty thousand of them entered Thrace and were beaten in detail by his friend the young Andronicus. [Sidenote: Capture of Brousa, 1326.] Weakened by having to meet this huge northern army, for huge it must have been, although the number of the invaders is probably exaggerated,[50] the young emperor was forbidden or was unable to go to the relief of Brousa when, two years afterwards, Othman laid siege to that city. Its surrender in 1326 is a convenient mark of the progress made by the Ottoman Turks. Their great leader, Othman, died in the following year. CHAPTER IV DYNASTIC STRUGGLES IN EMPIRE: APPEALS TO POPE FOR AID; REIGNS OF ANDRONICUS THE SECOND, JOHN CANTACUZENUS AND JOHN; REPEATED FAILURE OF EFFORTS BY POPES TO INDUCE WESTERN POWERS TO ASSIST IN CHECKING MOSLEM ADVANCE. When, in 1320, the Emperor Michael the Ninth died, the empire was already threatened by large and ever-increasing armies of Asiatics, both on the north and on the south. Those on the south were steadily being incorporated into the group ruled over by Othman. The sixty years which had passed since the expulsion of the Latins had nevertheless done something, though not much, towards restoring the empire. Territory had been recovered. The walls of the capital had been repaired. The population had begun once again to look to the emperor at Constantinople as their natural ruler.[51] [Sidenote: Distressed condition of the empire.]