Chaillé-Long (1842-1917) fought in the American Civil War before joining the Egyptian army as a lieutenant-colonel in 1869. He later accompanied General Charles G. Gordon on an expedition from Egypt into Sudan, during the course of which Chaillé-Long continued to Uganda. On his return he discovered Lake Kioga, one of the lakes through which the While Nile flows. He subsequently undertook further expeditions in Africa, departing the Egyptian service in 1877. He returned to Egypt on several further occasions, but also trained as a lawyer, teaching international law in Paris, and became consul general for the delegation to Korea. His later career was marked by disappointment that his explorations did not receive the recognition in the English-speaking world that they deserved, and the preface to the present work exhibits his bitterness in this regard. He dedicates the volumes to the memory of General Gordon.