In this paper the author argues that urbanisation should be understood as a global historical process driven primarily by population dynamics stimulated by technological and institutional change. In particular, disease control and expanded access to surplus energy supplies are necessary and sufficient conditions for urbanisation to occur given historical evidence of an inherent human propensity to agglomerate. Economic development, which has traditionally been viewed as the primary driving force behind urbanisation, can accelerate the process but is not a necessary condition for it to occur. Informed by this historically-grounded theory of urbanisation, a range of qualitative and quantitative evidence is used to explain the stylised facts of sub-Saharan Africa's urban transition, namely the late onset of urbanisation in Africa vis-a-vis other major world regions, the widely noted but inadequately explained phenomenon of 'urbanisation without growth' observed in Africa in the 1980s and 1990s, and the historically unprecedented rates of urban population growth seen in the region throughout the late twentieth century.
Working Paper No. 89 (series 2), London, UK; Crisis States Research Centre, 32 pp.