And before we call our glorious Greco-Roman past objectively more humane and kind... well, I think there is a building in Rome or 2 standing as testaments to brutality and sadism.
Not just Rome-the Druids in Britain put people in wicker cages suspended over a fire to roast as a sacrifice. In Norway, people were sacrificed by slow strangulation and being tossed in a bog, the Vikings raped and strangled a female slave as a sacrifice and set her off in the funeral boat with the dead war leader who owned her. Etc, etc, etc...
As Tacitus has the Briton Calgacus say, “The Romans create a desert and call it peace.” Caesar’s conquest of Gaul in the 50s B.C. may have cost 1 million Gauls their lives. They were ruthless to others who resisted their conquests including the Spanish, the Greeks and the Jews. Earlier the Greeks were pretty ruthless killing or enslaving defeated enemies, whether Greeks or barbarians.