The Annals of Kwangtung thus record the coming of the first Muslims into China:—“At the beginning of the Tʼang dynasty there came to Canton a large number of strangers, from the kingdoms of Annam, Cambodia, Medina and several other countries. These strangers worshipped heaven (i.e. God) and had neither statue, idol nor image in their temples. The kingdom of Medina is close to that of India, and it is in this kingdom that the religion of these strangers, which is different to that of Buddha, originated. They do not eat pork or drink wine, and they regard as unclean the flesh of any animal not killed by themselves. They are nowadays called Hui Hui. [962]... Having asked and obtained from the emperor permission to reside in Canton, they built magnificent houses of a style different to that of our country. They were very rich and obeyed a chief chosen by themselves.” [963] Though direct historical evidence is lacking, [964] it is most probable that Islam was first introduced into China by merchants who followed the old-established sea route. But the earliest record we can trust refers to diplomatic relations carried on by land, through Persia. When Yazdagird, the last Sāsānid king of Persia, had perished, his son, Fīrūz, appealed to China for help against the Arab invaders; [965] but the emperor replied that Persia was too far distant for him to send the required troops. But he is said to have despatched an ambassador to the Arab court to plead the cause of the fugitive prince—probably also with instructions to ascertain the extent and power of the new kingdom that had arisen in the West, and the caliph ʻUthmān is said to have sent one of the Arab generals to accompany the Chinese ambassador on his return in 651, and this first Muslim envoy was honourably received by the emperor. In the reign of Walīd (705–715), the famous Arab general, Qutaybah b. Muslim, having been appointed governor of Khurāsān, crossed the Oxus and began a series of successful campaigns, in which he successively subjugated Bukhārā, Samarqand and other cities, and carried his conquests up to the western frontier of the Chinese empire. In 713 he sent envoys to the emperor, who (according to Arab accounts) dismissed them with valuable presents. A few years later, the Chinese Annals make mention of an ambassador, named Sulaymān, who came from the caliph Hishām in 726 to the Emperor Hsuan Tsung. These diplomatic relations between the Arab and the Chinese empires assumed a new importance at the close of this emperor’s reign, when, driven from his throne by a usurper, he abdicated in favour of his son, Su Tsung (A.D. 756). The latter sought the help of the ʻAbbāsid caliph, al-Manṣūr, who responded to this appeal by sending a body of Arab troops, and with their assistance the emperor succeeded in recovering his two capitals, Si-ngan-fu and Ho-nan-fu, from the rebels. At the end of the war, these Arab troops did not return to their own country, but married and settled in China.