The Igbo people traditionally maintain a system of discrimination from the Odinani religion that discriminates against a class of people known as Osu (Igbo: outcast). Osu are regarded to be spiritually inferior beings, and they are distinguished from Nwadiala or diala (Igbo: real born). They are ostracized from wider society and Igbo are discouraged from marrying them. They were historically either sold into slavery or were delivered to be enslaved to certain deities who were believed to ask for human sacrifice during festivals in order to clean the land from abomination, thus leading to the purchase of a slave by the people.
