with how many ancient cultures sacrificed animals and sometimes people, what would happen with the bodies when they were finished? How would they know their sacrifices were accepted?
Is there any accounts on what would happen afterward?
This is bordering more or less in the realm of anthropology. I would suggest looking to Rene Girard and his theory of mimetics and scapegoating to understand the function of sacrifice to culture. He does a 5 part interview series with CBC that is fantastic and will give you a much broader understanding of culture and sacrifice. I've only read one of his books and it was very good despite being rather complicated.