William W. Hallo, former Yale professor, considers ancient Mesopotamia to be the point of origin of animal sacrifice. Hallo writes, "Here we have not only, as in Israel, the canonical (literary) formulations of how sacrificial rites are to be performed, but also economic texts providing accounts of events after the ritual and objectively recorded, detailing the expenses of each step in the ritual against the possibility of a future audit by a higher authority. These records leave no doubt that in Mesopotamia, animal sacrifice, though ostensibly a mechanism for feeding the deity, was at best a thinly disguised method for sanctifying and justifying meat consumption by human beings—a privilege routinely accorded to priesthood, aristocracy and royalty, and sporadically, notably on holidays and holy days, to the masses of the population."
Among meat eaters, the blood of hunted animals was not wasted. It would replace the costly red ocher. Eventually, sacrificial rituals developed around the bloodletting. The French historian Jean-Pierre Vernant believed the distribution and consumption of sacrificial food was a way to bound a community together, with each member of the community consuming an equal portion of meat. However, it is also possible that the chief, as a representative of the High God on earth, received a more substantial or better portion of the meat.
Among the early Hebrew (c. 5000-2000 BC) animal sacrifice was performed only in cases of extremely grave offenses. Cattle and sheep were their source of wealth, so they did not sacrifice them often. It is possible also that animal sacrifices were offered at times of crisis or when a leader needed a sign from the High God. This appears to be the case with Abraham on Mount Moriah. There he was given the sign of the Ram which for him was a Messianic promise.
In the Axial Age (900-200 BC) Jewish and Hindu priests were paid to offer sacrifices. Greed among corrupt priests led to the slaughter of enormous numbers of animals. Blood flowed in the temples and through the drainage ditches. Buddha rejected animal sacrifice. Buddhism is an attempt to reform this feature of Hinduism.