In their initial interaction with the Colonial powers, several East African peoples such as the Maasai, the Turkana, the Sebei, the Karamojong, and the Nandi—all organized through some type of age-based institution—united around prophetic leaders, diviners, or ritual experts who mobilized men from several territorial sections to confront the intruders. This ad hoc military unity was necessarily short-lived, usually ending with the defeat of the people by the colonial power and see the imprisonment or death of the prophetic leader involved. (See Fosbrooke 1948: 12-19; Merker 1910: 67-105; Jacobs 1965: 20-108; Dyson-Hudson 1966: 15-16; Gulliver 1950: 229, 240; Meinertzhagen 1956: 222 ff; Weatherby 1962: 200-12; 1967: 133-44; Lamphear 1976: 225-43.) While ethnological studies of various age-organizations often mention that diviners or prophets provided professional services for the members of an age-group at their ceremonies, no one has examined the process by which a prophetic leader or diviner established his legitimacy during periods of peace so that he might lead the people during times of crisis. An examination of the prophetic institution among the Maasai and the relationship between the prophets and the members of the age-sets may provide some insight into the process, especially the manner in which prophets emerged as leaders of the people during two major crises in the history of the Purko-Kisongo Maasai: the Ilaikipiak war and the rinderpest pan-zootic.