The Mau Mau movement wrought violence on Kenya for much of the 1950s (see map 1 for Kenya Colony). Confined mainly to the Kikuyu, Embu and Meru tribes of the central highlands, unrest had been gathering pace for several years before the government declared an official State of Emergency in October 1952. The rebellion was devolved and complex in organisation and motivation. A large number of grievances were involved, ranging from an anti-colonial desire to expel Europeans, to dissatisfaction with imposed agricultural techniques. Probably the most important single cause of the revolt was the belief that the Kikuyu had been cheated out of their rightful lands by European settlers. Despite the anti-colonial dimension, the conflict is normally now described as a civil war within the Kikuyu, as the squatters (temporary workers on European farms) fought against the landed establishment. Important alliances were forged between the rural dispossessed and urban activists in Nairobi.

The rebellion was limited geographically, mainly to the Central and Rift Valley Provinces, and to Nairobi (see map 2). So in most of Kenya life carried on as normal during the Emergency. Out of a total African population of around 5 million, the 1.4 million Kikuyu were nearly all considered unreliable by the government. At this point the Asian community in Kenya stood at about 97,000, and the European settlers at 29,000. The settlers dominated local politics, and there was no democracy for the Asians or Africans in the country. The origins of the conflict can be seen in the Kikuyu's poor economic conditions, the lack of political representation, and a growing land hunger as the population mushroomed. Perhaps the most convincing account of the brewing troubles argues that these causes prompted three political blocs to emerge by the 1950s. The conservative element in Kikuyu society comprised chiefs, headmen and senior Christian elders, who believed in supporting the colonial project. The moderate nationalists, such as Jomo Kenyatta and Koinage wa Mbiyu, were westernized, believing in social progress and political representation. These moderates formed such groups as the Kikuyu Central Association and later the Kenya African Union. The third group, the militant nationalists, first appeared in the 1930s. They gave shape to the Mau Mau in the 1950s and grew more influential as the failure of the moderates to achieve any meaningful progress became obvious. By 1952 Mau Mau attacks on settler property and on perceived collaborators were becoming widespread in Kikuyuland.