 Similarly, within the Roman Empire, which is considered as one of the most multi-ethnic empires, cultural difference was usually integrated into the predominant culture, whereas biological hybridity was condemned.The Romans’ attitudes to racial mixing hardened from the 4th century AD when Rome embraced the Christian faith.This is manifest in the Codex Theodosianus (AD365) which prohibited marriages between Christians and non-Christians, the Jews in particular, and inflicted death penalty on those who did not obey this law.