They are completed by the Forest Books, [=A]ranyakas, which contain the speculations of the later theosophy, the Upanishads (below).

It is with the Yajur Veda and its nearly related literature, the Br[=a]hmanas, that Brahmanism really begins.

Of these latter the most important in age and content are the Br[=a]hmanas (of the Rig Veda and Yajur Veda), called [=A]itareya and Cata-patha, the former representing the western district, the latter, in great part, a more eastern region.
Although the 'Northerners' are still respectfully referred to, yet, as we have just said, the people among whom arose the Br[=a]hmanas are not settled in the Punj[=a]b, but in the country called the 'middle district,' round about the modern Delhi.

For the most part the Punj[=a]b is abandoned; or rather, the literature of this period does not emanate from the Aryans that remained in the Punj[=a]b, but from the still emigrating descendants of the old Vedic people that used to live there.

Some stay behind and keep the older practices, not in all regards looked upon as orthodox by their more advanced brethren, who have pushed east and now live in the country called the land of the Kurus and Pa[.n]c[=a]las.[5] They are spread farther east, along the banks of the Jumna and Ganges, south of Nep[=a]l; while some are still about and south of the holy Kurukshetra or 'plain of Kurus.' East of the middle district the Kosalas and Videhas form, in opposition to the Kurus and Pa[.n]c[=a]las, the second great tribe (Tirh[=u]t).