of food supply. It dramatically increased the
be used for travelling long distances and for carrying goods as pack animals
in much less time. The great speed and physical strength of the horse
enormously increased the war potential of its users. Whatever be the
equipment of the non-horse users in the late Neolithic or Bronze Ages, they
could be easily overcome by the horse users. Since the Indo-Europeans were
great horse users, they spread rapidly in the late third and second millennia
BC. The possession of the horse and chariot gave rise to a horse-centred
aristocracy which provided leadership to the community. Thus, the
introduction of the horse initiated the process of social differentiation in
previously egalitarian communities.
Animal Sacrifice
Animal sacrifice may have been more important in the initial stage of
stockbreeding: So long as the cattle rearers do not use dairy products and
employ animals in agriculture and transport, they continue to eat the meat of
their domesticated animals. The cattle rearers offered meat to their gods and
in return asked for cattle wealth so that their practice of sacrificing cattle and
eating meat might continue. The cattle sacrifice of the Vedic period was
called pasubandha.
    There is provision for the sacrifice of cattle, horse, sheep and even pigs in
Vedic literature. The Satapatha Brahmana contains all these instances. The
same text also lists certain categories of human beings and animals
considered unfit for sacrifice. This list includes impotent persons, gaura (a
kind of buffalo), aranya (wild animal), ustra (camel) and sarabha (elephant).
    In Vedic times, the king or the chief performed the asvamedha to assert
his suzerainty. A horse was set free and the territory traversed uninterrupted
by it and the warriors of the chief/king, was considered to have fallen under
the sway of the royal sacrificer. On its return, the horse was sacrificed and its
body dismembered. The king’s favourite wife had to lie down with the dead
horse, and ‘cohabit’ with it under covers. There is no evidence of the horse
sacrifice in pre-Vedic India.
Fire Cult and Fire Altar
The cult of fire is the most significant  cult in the Avesta, but although Agni is