Christian symbols with indigenous symbols. Among these was the Aladura (prayer) movement that was spreading rapidly throughout Yoruba land and into the non-Muslim middle belt areas. Missionary work Apart from Benin and Warri, which had come in contact with Christianity through the Portuguese as early as the 15th century, most missionaries arrived by sea in the 19th century. As with other areas in African continent, Roman Catholics and Anglicans each tended to establish areas of hegemony in southern Nigeria. After World War I, smaller denominations such as the Church of the Brethren (as Ekklesiyar Yan'uwa a Nigeria), Seventh-day Adventists and others worked in interstitial areas, trying not to compete. Although less well-known, African-American churches entered the missionary field in the 19th century and created contacts with Nigeria that lasted well into the colonial period. Also, during this period, Jehovah's Witnesses began their missionary work in Nigeria and soon spread throughout the country Offshoots of European denominations African churches were founded by small groups breaking off from the European denominations, especially in Yorubaland, where such independence movements started as early as the early 19th century—influenced by American and British missionaries in early 1900s and stimulated by the great revival of the 1930s. They were for the most part ritually and doctrinally identical to the parent church, although more African music, and later dance and dressage/vesture, entered and mixed with the imported church services. Notable among the new springs of 1930 were such Protestant Pentecostals as the Christ Apostolic Church—an offshoot of US-based Faith Tabernacle which swept through the Western Region and complemented by the likes of the Celestial Church and the Cherubim and Seraphim Church which were indigenous autonomous springs. A number of indigenous denominations used Biblical references to support polygamy. With political independence came African priests in both Roman Catholic and Protestant denominations. Rituals and forms of worship were strictly those of the home country of the original missionaries. By the 1980s, African music and even dancing were being introduced quietly into western oriented church services, albeit altered to fit into rituals of Euro-American origin. Southern Christians living in the north, especially in larger cities, had congregations and churches founded as early as the 1920s. Even medium-sized towns (20,000 persons or more) with an established southern enclave had local churches, especially in the middle belt, where both major religions had a strong foothold. The exodus of Igbo from the north