Род Сакья не упоминается в Ведах, по-видимому, они пришли в Индию с Запада после ведийского периода, а затем переселились в восточную Индию задолго до времени жизни Будды.
http://en.wikipedia.org/wiki/Shakya
Индолог Майкл Витцель предполагает, что переселение Сакьев было одним из первых вторжений Скифов (Саков) в Индию.
Both the Malla and Vr ji apparently immigrated into the east only after the end of the Vedic period, but well before the time of the Buddha (c. 400 B.C.). This must have been one of the last great infiltrations in Vedic times of western peoples into the lower Gan gå area. More or less about this time the so-called second urbanization began as well.
Nevertheless, the settlement pattern in the east was not as homogenous as it was in the more western areas where the indigenous population had become Indo-Aryan in language and culture since the Mantra period. Instead, the Kosala-Videha area was one of great mixture of peoples. There were some earlier eastern Indo-Aryan settlers, the local Munda people and some Tibeto-Burmese elements. Then, various types and groups new immigrants entered from the areas further west. These were some brahmanically oriented tribes but also other non-orthoprax Indo-Aryan tribes such as the Malla and V rji. They immigrated from northwestern India into Bihar which had been already settled by the old, para-Vedic Indo-Aryan tribes such as the Iksvåku, Kosala, Kåśi, and Videha.
Many of these tribes, including the Śakya to whom the Buddha belonged, are called asurya in ŚB. For it is the Sakya and their neighbors, the Malla, Vajji, etc. who are reported in the Påli texts as builders of high grave mounds, such as the one built for the Buddha. According to ŚB 12.8.1.5 the “easterners and others(!)” are reported to have round “demonic” graves, some of which may have been excavated at Lauriya in E. Nepal. These graves are similar to the kurgan type grave mounds of S. Russia and Central Asia. However, the origin of the Śakya is not as clear as that of the Malla and Vr ji. They may very well have been (northern) Iranian, and would then constitute an earlier, apparently the first wave of the later Śaka invasions from Central Asia.
http://www.people.fas.harvard.edu/~witzel/canon.pdf#page=56
http://groups.yahoo.com/group/Indo-Eurasian_research/message/13470
Possible Iranian Origins for Sākyas and Aspects of Buddhism
Jayarava Attwood
http://www.ocbs.org/ojs/index.php/jocbs/article/view/26
http://jayarava.blogspot.com/2012/02/possible-history-for-buddhist-idea-of.html
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