Language Log discusses a paper looking at the spread of wool and wool related technologies in Bronze Age Asia. The bottom line chronology is as follows:
—After 3300 calBC: early exchanges of prestige goods across Near East and the North Caucasus, with wool-cotton textiles moving as part of the elite exchange networks; mixed wool-cotton textile dates around 2910–2600 calBC.—The mid third millennium BC: spread of wool textile technologies and associated management out of the Near East / Anatolia and into the southern Caucasus; according to 14C data obtained for textiles and synchronous samples this happened between 2550–1925 calBC; an almost synchronous date was obtained from the dates of the northern steppe regions, suggesting that the spread of innovative technology from the South Caucasus to the steppe zone and further north up to the forest zone occurred as part of the same process between 2450–1900 calBC.—Between 1925–1775 calBC there was rapid eastward transmission of the wool (and associated technologies) across the steppe and forest-steppe of the Volga and southern Urals, out across Kazakhstan and into western China between 1700–1225 calBC. This same process of transmission through the steppe ultimately brought woven wool textiles into societies around the western Altai and the Sayan Mountains of southern Siberia.
The Language Log post continues by observing that:
The findings for the timing and spread of wool technology comport well with those for bronze, chariots, horse riding, iron, weapon types, ornamentation and artwork, and other archeologically recovered cultural artifacts that we have examined in previous posts. Moreover, they are conveniently correlated with archeological cultures such as Andronovo[.]