Twelve years earlier Timur had been a minor member of the Barlas tribe, one of many tribes in the western part of the Chagatai Khanate. Since the 1330s the Khanate had been split in two, between Mawarannahr (Transoxiana) in the west and Moghulistan in the east. Between 1347 and 1358 Mawarannahr was ruled by Amir Qazaghan, but in 1358 he was assassinated on the orders of Tughlugh Timur, Khan of Moghulistan. This was followed by an invasion from Moghulistan. Hajji Beg, ruler of the Barlas tribe, decided to flee, but Timur offered his services to the Moghuls, as a result becoming head of the tribe. During this period Tamerlane formed an alliance with Amir Husayn of Balkh, a grandson of Qazaghan, marrying his sister.