Human African trypanosomiasis, better known as sleeping sickness, nowadays ranks among the more neglected diseases in the countries of Africa where it is found. Though it still kills many people every year, it cannot compete for celebrity with such major killers as malaria and AIDS. Yet that was not always the case. A hundred years ago, sleeping sickness attracted considerable scientific research and political attention because of its importance to the conquest of sub-Saharan Africa by the European colonial powers. The goal of this paper is to describe the nature of the sleeping sickness epidemics that afflicted East and Central Africa in the early 20th century, the efforts made by European scientists to understand the disease and find means of controlling it, and the differences between the methods used by the British, Belgian, French, German, and Portuguese colonial authorities to combat it.