The region of West Africa currently delineated by the boundaries of the independent country of Nigeria has a long, rich, and complex history exhibiting dramatic political, economic, social, and cultural change over time. Archaeological evidence of indigenous communities dates back to at least 8000 bce. Early states and societies took a variety of different forms and developed significant interaction among each other and through long-distance trade networks in the savannahs and coastal regions. The 19th century saw the encroachment of British colonialism, which ultimately produced the territory of Nigeria in 1914. Nigeria achieved independence in 1960, but the country has been beset by significant political instability and economic underdevelopment. As a result, the process of developing a national historical narrative has been complex and contested in a country whose borders were largely established by alien colonial rulers and that has since been beset by a variety of internal divisions with differing relationships to Nigeria as a corporate entity. This complexity is reflected in the dynamics of Nigerian historiography and the primary source bases upon which historical scholarship has relied.