History of the Jews in Nigeria
The historic presence of Judaism in Nigeria is a cause of debate, as there are several Judaic-oriented religious groups among the largest ethnic groups in the largely populated nation. The groups claim that their religious practices result either from hundreds of years of continuous practice of Judaic or Judaic-like customs by their ethnic groups, customs inherited from the Jews of Bilad el-Sudan or by a more-recent departure from European Christianity to modern Judaism. Either way, Judaism in Nigeria has developed demographically with the interest of Jewish peoples in other countries, especially Israel and the United States.
The Igbo Jews of Nigeria are one of the components of the Igbo ethnic group.
Certain Nigerian communities with Judaic practices have been receiving help from individual Israelis and American Jews who work in Nigeria, out-reach organizations like Kulanu, and African-American Jewish communities in America. Jews from outside Nigeria founded two synagogues in Nigeria, which are attended and maintained by Igbos. Because no formal census has been taken in the region, the number of Igbos in Nigeria who identify as either Israelites or Jews is not known. There are currently 26 synagogues of various sizes. An estimated 30,000 Igbos were practicing some form of Judaism in 2008. 
Akwa Ibom and Cross River Jews
The Annang, Efik, and Ibibio people of Akwa Ibom and Cross River States of Nigeria have had ancient religious practices that strongly resembled some of the Jewish Torah. These include their traditional sacrifice of animals (rituals) by the presiding male of each village, or of a group of villages, for purification, especially during times of sickness. They have active synagogues with majority of the synagogues in the eastern part of the country a vibrant one in Abuja supported and provided with lots of Jewish materials by different Rabbis. There are also key Synagogues in Port Harcourt and Lagos.
The Jewish community among the Yoruba are often referred to as the Bnai Ephraim (Children of Ephraim). Most of them concentrated around various communities in Ondo state since the 1930s, about 2000 people in all. According to their traditions, they came to Nigeria by way of Morocco sometime in the 16th century after the expulsion of the Jews from Spain in 1492. Their language is a mixture of Moroccan Arabic with Yoruba, but with bits of Aramaic, such as ima for “mother.” Other Yorubas may call them Emo Yo Quaim – the “Strange People” as like in most ethnic groups, the practice of Judaism is among a very small minority. The Bnai Ephraim have kept portions of the Torah in their sanctuaries which distinguish them from their Igbo counterparts who practice Judaism without much influence from the Torah. 
- Kulanu website, especially relevant is the Nigeria page, which treats the Igbo question more extensively.
- Bruder, Edith (2008). The Black Jews of Africa: History, Religion, Identity. Oxford University Press. p. 143. ISBN 978-0195333565.
- Jews in Africa, this web page near the bottom discusses the Bnai Ephraim among the Yoruba people.