The Esan people are one of the largest ethnic groups in Edo state, Nigeria. A large percentage of Esan people are Christians, mostly Catholic but in recent times, other denominations have surfaced in the region.
Like most major and minor ethnic groups, the Esan people have their own gods, religions and traditions which is now practiced by only a few people as a result of Christianity and modernization in the land. The people believe in one Supreme God (Osenobua) who is the master of the earth. There are other gods that are immediate to them and through whom they can pass on their pleadings and requests to the Supreme Being. Such gods are deified in shrines adorned with statues and carvings where prayers and sacrifices are offered either in request for a dire need or in appreciation for a particular blessing. For instance, during a prolonged drought, they pray and sacrifice for rain and when there is peace and harmony in the community or a very bountiful crop harvest, they offer sacrifices in appreciation. 
Apart from this, there is a widespread belief that these intermediary gods can be appeased in times of distress, sickness or premonition in the community with appropriate sacrifices. They can also be manipulated to curse a real or imagined enemy or foe. Alternatively, disputants to an issue can go and swear an oath before the deity in order to prove their guilt or innocence.
ESAN GODS
Traditional Esan religion has many similarities to traditional Edo religion, due to the Esan migration to the Northeast during the 15th century from the Benin Empire. There are many deities of the Esan religion:

• OSANOBUA: Osanobua is the creator of the divinities, who are conceived of as his children; animals and man. He is known as the omniscient and also the controller of life. In Esan land, all births are attributed to him. Osanobua is the main Edo Esan god. He is also envisioned as a king living in a palace from which he presides over the spirit world, having delegated responsibilities to his children. This name for God was brought over by Christianity and its missionaries, and thus the translation for God in Esan land is Osanobua.
• OLOKUN: Olokun, ruler of the great waters, is the favoured son of Osanobua who is believed to have superseded the father and who can be approached in order to obtain favours from the father. He is a speaking and acting divinity; far more active than Osanobua, and not as remote. Olokun is interpreted as manifesting himself to the Esan people in four ways: through the dream experience, the possession experience, divination and through particular events. Olokun is said to be of a gentle nature and is never associated with anything evil or destructive (he never kills).
• ESU: The Esan people believe that Osanobua created Esu to declare war and for general destructive duty. Esu, known as the trickster god, is the arch enemy of Osanobua, the antithesis of goodness. Esu is also believed to be black and ugly and he wanders about restless and destructive. The “Azen” known as witches in Esan land are also linked to Esu because of their wickedness. It is said that the Azen is responsible for miscarriages, madness and fertility issues in the land, amongst other wicked acts. This Esu god is shared with Yoruba and Edo myth. The name Esu was used as a translation for Satan by Christian missionaries.
• OSUN: the Esan god of medicine. Osun, being the god of medicines, officiate ceremonies, perform sacrifices, lead songs and prayers and convey messages from a deity who “speaks” through them while they are dancing or in a trance. This is where the surname Okosun, or son of medicine, originated from.