In 1884, the General Act of Berlin Conference established borders of African colonies. Many of these “exogenous” borders brought about by Scramble of Africa could be still found on modern maps, now separating sovereign states. About one third of all countries of Sub-Saharan Africa – much larger portion compared to other parts of the world – are landlocked.
Since trade with other countries is important for economic development, and since transportation by sea is much cheaper than any other type of transportation, the evolutionary process of “endogenous” formation of the nation states in other regions left few countries without access to sea. It was not impossible, but certainly more difficult, to develop as a nation without such.