The cast was divided into two different tribes, the Ogakor and the Kucha.
Along the south foot of the Tian-shan, and in the high valleys which intervene between the constituent ranges of that system, there exist numerous flourishing oases, such as Uch-turfan, Ak-su, Kucha, Korla, Kara-shahr, Hami, Barkul, Turfan, Urumchi, Manas and Kulja.
The caravan routes mostly followed between China and the more populous centres (Kashgar and Yarkand) of East Turkestan start from An-si-chow and Sa-chow respectively, converge upon Hami on the north side of the Pe-shan swelling, and continue westward along the south foot of the Tian-shan Mountains through the oases of Turfan, Kara-shahr, Korla, Kucha, Ak-su and Uch-turfan.