This is one of most twisted, most misunderstood system in the whole of igbo land.

OSU is not the same with OHU: an Ohu is a slave, so let us not confuse ourselves with these two.

In Igbo land there are four types of Osu.
1, these are people who dedicate themselves, to the service of God. They are the servants of the Arụsị or servants of the sanctuary of the community Arụsị, they are separated from the community. They are dedicated to the service of their God, they live by what comes to the Arụsị. They neither have inheritance among their communities, and this is from generation to generation. It was a revered institution in precolonial igbo societies.
They were revered among igbo communities, because they are the mouth piece of the Gods. Too they live by the highest moral and ethical standards, they are incorruptible. A man of the house will tremble if an Osu suddenly appears in front of his house, because he knows that he or she has brought massage from the Gods.
If OSU is as bad as we relate them today in Igbo land, why do we have people with Surnames like these: Ezenwosu, Nwosu, Osuji1, Osuala, Osuigwe, Osuagwu, Osueke, Osungwe, Osuama etc. I can go on, it is a fact that if Osu was evil and repudiated in igbo land. These families will not associate themselves with these names, because nobody can openly identify him or herself with evil. Osu is actually a prefix names, to a person who distinguishes him or herself in any field. For example Osuji is a name to the person who cultivates the biggest yam for a given period. So the person will be called Osuji and so on.

2, the second type of OSU in igbo land, are those who are persecuted. Either a widow with her children, who the family members of her late husband. Are trying to take over there properties, or some people who for some reasons are persecuted by people more powerful than them. These kind of people normally run to Arụsị, for protection for them, their families and all their properties. Like this they are protected from all attacks, because nobody dare touch them if they are under the protection of Arusi/shrine.

3, this third type are people who are brought home from wars, when they are captured and taken as prisoners of war. They are dedicated to the sanctuary of the Arụsị, normally one of their ears are cut and with the blood they are thus dedicated to the Arụsị. Osu ebere nti(Osu that the ear is cut). They will be given some portion of land, to settle down in the community. Them and their descendants are Osu forever, they serve special purpose in igbo communities.

4, these are people who either intentionally or unintentionally, crossed the space between the outer space and inner sanctuary of the temple of the Arụsị. Whoever crosses this point automatically becomes an Osu. Because only the priest is allowed or has the authority to cross that point.

These are the classes of OSU in igbo land, people actually has little or no knowledge about OSU CAST systems.

When I see some ignorant people talk about OSU, I usually laugh at their hypocrisy and ignorant. Because in igbo land, if you eat with an OSU in the same place. Automatically you become an OSU, so also is the case. If you touch them, sleep with them, have sex with them, if you cross a stretched leg of an Osu. So my question is, all you the people you had befriended, talked to, eaten with, do you know if they are Osu?????. Because if you had done any of these things you toois an Osu, because people only talk about Osu when they want to get married. This to me is the height of hypocrisy, because some had actually befriended the person in question before they discovered that the person is an Osu.
Another important factor today in igbo land is that, some of the richest people in igbo land are Osu. So why did God of Ndi Igbo decide to bless the outcast more than the free born???

One will then ask why, when and how did OSU become evil in igbo land???.
When the missionaries came into the hinterland of the Eastern region, they met a well organised societies. That were governed by invincible principles, order and high moral standards. So they knew that for them to defeat these people, they had to destroy their base. Which in this case is their culture and traditions, they first destroyed the Eze Nri who was the back bone of the igbo culture and traditions. Then they went after the Osu who are another important part of the system, they demonised them and prohibited any Christian to associate with them. As many igbo became Christians, the Osu was each time treated like a desease.
The social outcast, exclusion, prohibition, distancing and isolation, is as the result of Christians seeing them as evil.
So the Christians created the outcast of Osu system in Igbo land we see today.
A typical example of this today is the Nze/Ọzọ tittle, not long ago. If you take Nze/Ọzọ tittle in Igbo land, you will be excommunicated from your church. Many people out fear of this renounced, denounced their titles in other to belong to the church. After the Christians has successfully destroyed the institutions of Nze/Ọzọ in Igbo land. People are now allowed to take the title but in the Christian form (Ọzọ ndị ụka) the Christian Nze/Ọzọ. Only very very few communities in igbo land still have the original system of this institution.

So Osu cast system is the creation of Christianity in igbo land, about 90% of igbos are Christians. And this has affected the equilibrio, spirituality, moral and culture of ndị Igbo.

Today in Igbo land it is common happening to see a pastor/ priest, to ask his members to burn down these sacred places of worship all over igbo land. Because according to them these are the cause of poverty and lack of opportunity for these teeming youths.
This is the genesis of overall problem of Ndi Igbo, they were brain washed to fight and destroy their essence. And today go to any church in any part of Nigeria, 70 % of the members are igbo, looking for praying for miracles. They are the most vulnerable race in all the black communities, because they had destroyed the foundations of their existence. These is the reason that anyone among, who has the courage to look back to the ways of the old, is always full of joy. Miracle happens instantly in the life of the person, because he or she has reconnected back to his essence.