People sent out to carry a religious message in hopes of converting them are called

The answer is missionary. A Christian missionary can be well-defined as "one who is to spectator across cultures". The Lausanne Congress of 1974, demarcated the term, connected to Christian mission as, "to create a feasible indigenous church-planting drive”. Missionaries can be located in many countries all over the place in the world.

it depends on which society you are referring to. many civilization performed rituals so the gods would with their growing season but the most well known is that of the aztecs. they would make sacrifices, usually animals, but sometimes humans as well.