In Temples, the Romans would have worshipped their various god and things like that
animals
For the most part of their history, the Roman leaders were concerned that their gods would withdraw their support. That's why they sacrificed to them and honored them with their various festivals and temples.
According to Roman and Greek sources, Phoenicians and Carthaginians sacrificed infants to their gods.
In Christianity, Jesus Christ is said to have sacrificed himself. In Greek and Roman, there have been numerous sacrifices for numerous reasons, both by gods and demi-gods.
The gods were supposed to be benign if good things were sacrificed to them.
They sacrificed themselves.
The Vikings sacrificed animals and sometimes humans for their gods.
They sacrificed one another because when one sacrificed to them it was an honor.
Roman Coliseum, in short was used for blood sport dedicating the lives sacrificed to the gods. Imagine any sport resulting in death. The romans did it first.
The Aztecs sacrificed slave and volunteers to please their gods
They sacrificed animalsthey prayed
They used them as slaves or sacrificed them to the gods.
In the Mayan ballgames...the losing team would be sacrificed to the Mesoamerican gods and goddesses.