Like so many other African  states, Nigeria is the creation of European imperialism. Its very name after the great Niger River the country's dominating physical feature was suggested in the 1890s by British journalist Flora Shaw who later became the wife of colonial governor Frederick Lugard. The modern history of Nigeria as a political state encompassing 250 to 400 ethnic groups of widely varied cultures and modes of political organization dates from the completion of the British conquest in 1903 and the amalgamation of north and south Nigeria into the Colony and Protectorate of Nigeria in 1914. The history of the Nigerian people extends backward in time for some three millennia.

There are several dominant themes in Nigerian history that are essential in understanding contemporary Nigerian politics and society. First the spread of Islam predominantly in the north but later in southwestern Nigeria as well began a millennium ago. The creation of the Sokoto Caliphate in the jihad (holy war) of 1804-8 brought most of the northern region and adjacent parts of Niger and Cameroon under a single Islamic government. The great extension of Islam within the area of present-day Nigeria dates from the nineteenth century and the consolidation of the caliphate. This history helps account for the dichotomy between north and south and for the divisions within the north that have been so strong during the colonial and post-colonial eras.

Second the slave trade both across the Sahara Desert and the Atlantic Ocean had a profound influence on virtually all parts of Nigeria. The transatlantic trade in particular accounted for the forced migration of perhaps 3.5 million people between the 1650s and the 1860s while a steady stream of slaves flowed north across the Sahara for a millennium ending at the beginning of the twentieth century. Within Nigeria slavery was widespread with social implications that are still evident today. The Sokoto Caliphate for example had more slaves than any other modern country except the United States in 1860. Slaves were also numerous among the Igbo the Yoruba and many other ethnic groups. Indeed many ethnic distinctions especially in the middle belt--the area between the north and south--were reinforced because of slave raiding and defensive measures that were adopted for protection against enslavement. Conversion to Islam and the spread of Christianity were intricately associated with issues relating to slavery and with efforts to promote political and cultural autonomy.

Third the colonial era was relatively brief lasting only six decades or so depending upon the part of Nigeria but it unleashed such rapid change that the full impact was still felt in the contemporary period. On the one hand the expansion of agricultural products as the principal export earner and the corresponding development of infrastructure resulted in severely distorted economic growth that has subsequently collapsed. On the other hand social dislocation associated with the decline of slavery and the internal movement of population between regions and to the cities necessitated the reassessment of ethnic loyalties which in turn have been reflected in negligence and poverty.