George Van Driem is a proponent of the theory that the Eastern Himalayas and Bhutan served as a “central staging area” for the peopling of East and South East Asia. Van Driem writes: “The Eastern Himalaya can be identified as a cradle of ethnogenesis and a principal thoroughfare in the course of population prehistory.”
According to Van Driem, “the region comprising Nepal, Sikkim, Bhutan, southeastern Tibet and northeastern India, furnished the cradle for the ethnogenesis of all East Asian language families: Trans-Himalayan, Hmong-Mien, Austroasiatic and Austro-Tai. At even greater time depths, the Uralo-Siberian and Altaic linguistic phyla too may have ultimately originated in the Eastern Himalaya.”
This article excerpted below from The Eastern Himalayas and the Mongoloid myth authored by George van Driem, offers a fresh narrative of the expansion and great migration of a paternal ancestral lineage that has formed a large component of many of the populations in East Asia – it is an account that differs greatly from the usual Han Chinese-Mongoloid ancestry account.
This account of the ethnogenesis of O2b and O3a3c in particular are relevant to the peopling of Japan after the Jomon period. Studies have shown the two Y-DNA haplogroups entered Japan from Northern Kyushu, taking different routes from west to the east. O2b1 (which forms around 22% of the Japanese (male) population) shows up strongest in Fukuoka, then Nagasaki, Tokushima, Kanazawa and Sapporo, while 03a3c shows up lower in Fukuoka but stronger in Kawasaki.