Through the start of the twentieth century Kenya was settled by Europeans who created businesses in the fertile central highlands, mainly farming coffee and tea. They displaced large numbers of the Kikuyu tribe who had worked the land as migratory farmers for centuries. When Kenya became a crown colony of the British Government in 1920, the settlers were able to introduce a number of restrictions on land ownership and agricultural practice in order to protect their own interests and push the Kikuyu out.

During the early 1950s, resentment grew amongst the Kikuyu tribe against European settlement, their lack of political representation, low wages and access to land.

By 1951, information was filtering back about secret meetings being held in the forests outside Nairobi and a secret society called the Mau Mau was formed. It required its members to take an oath to drive the white man from Kenya. It was suggested that membership of the Mau Mau was initially restricted to members of the Kikuyu tribe, many of whom have been arrested during burglaries in Nairobi’s white suburbs. Tensions escalated the following year when the Kenyan government imposed a curfew in three districts on the outskirts of Nairobi where gangs of arsonists, believed to be members of the Mau Mau, have been setting fire to homes of Africans who refuse to take the Mau Mau oath.

Later in 1952, Senior Chief Waruhui, who was a supporter of the Colonial British presence in Kenya was murdered triggering British troops being sent to Kenya. Further murders followed and a State of Emergency was declared. Suspected Mau Mau activists began to be arrested as did Jomo Kenyatta, president of the Kenya Africa Union and the country’s leading nationalist leader, who was charged with managing the Mau Mau terrorists. He is later sentenced to nine years hard labour. Far from quelling unrest, open rebellion against the British was declared by the Mau Mau. Further suspects were arrested by the British in larger numbers and the British imposed the death penalty on anyone who took the Mau Mau oath.

British military operations started to concentrate on areas where Mau Mau was most active. These included ‘Operation Anvil’ in Nairobi in April 1954, the mass screening, arrest and detention of huge numbers of Mau Mau and its supporters. Large-scale sweeps took place in the Aberdare and Mount Kenya areas during 1955. Figures vary widely but suggest upto 150,000 kikuyu tribesmen where arrested and upto 13,000 people were killed, mainly on the Kikuyu side. Those arrested were detained in prison camps with rudimentary sanitation, little food and brutal disciplinary regimes involving hard labour, torture and mutilation.

A programme of ‘villagisation’ was followed where hundreds of thousands were forcibly removed from their villages to live in ‘protected villages’ which were lined with barbed wire and spike-bottomed trenches, watched by Home guard. The inhabitants were used as labour to grow food and work on infrastructure projects such as the construction of Embakasi Airport. Those who refused were punished with homes being destroyed or livestock being killed.

Attempts to end the conflict were made, with an Amnesty offered to the Mau Mau that if they surrendered they would be imprisoned but spared the death penalty. The offer was unsuccessful and was subsequently withdrawn allowing Mau Mau prisoners to face the death penalty.

Operations continued until 1959 when the British had largely gained control and the State of Emergency ended. Jomo Kenyatta was released in 1961 and African nationalist leaders agreed to take a role in forming a new Kenyan Government. It has been argued that the conflict helped set the stage for Kenyan independence in December 1963 or at least secured the prospect of Black-majority rule once the British left.