Land-use history, not readily available for most places, remains the weakest link in nearly all studies of historic vegetation change, in Africa as well as other places in the world. Notwithstanding, communities hold a great wealth of knowledge on the processes and events influencing change on the land they occupy. The Lambwe Valley, southwestern Kenya, has a multi-ethnic population of settlers from the early 1950s. These people have seen the transformation of an initially forested area with diverse challenges to their survival, to present-day scramble for the remaining high potential land. A large part of the forces driving human settlement and consequent changes in land-use and cover is attributed to the control of tsetse and trypanosomosis. The application of a socio-economic method of mapping land-use change with the participation of the community in this study depicted trends and the underlying causes. The control of tsetse fly and therefore trypanosomosis infection was significant in driving the changes in the valley. Agricultural intensification is suggested as a means to support the resultant higher populations of people and livestock