The population is divided into approximately 42 ethnic groups, among which discrimination and occasional violence were frequent. The 2009 census released in August 2010 revealed that the major ethnic communities were: Kikuyu, 6.6 million; Luhya, 5.3 million; Kalenjin, 5 million; Luo, 4 million; Kamba,
3.9 million; Kenyan Somali, 2.3 million; Kisii, 2.2 million; and Mijikenda, 1.9 million. The Kikuyu and related groups dominated much of private commerce and industry and often purchased land outside their traditional home areas, which sometimes resulted in fierce resentment from other ethnic groups. The numerically small and shrinking South Asian community controlled a disproportionate share of commerce.
Many factors contributed to interethnic conflicts: long-standing grievances over land tenure policies and competition for scarce agricultural land, the proliferation of guns, the commercialization of traditional cattle rustling, the growth of a modern warrior/bandit culture (distinct from traditional culture), ineffective local political leadership, diminished economic prospects for groups affected by a severe regional drought, political rivalries, and the inability of security forces to adequately quell violence. Conflict between land owners and squatters was particularly severe in Rift Valley and Coast provinces, while
competition for water and pasturage was especially serious in the northern districts of Rift Valley and Eastern provinces and in North Eastern Province.
In private business and in the public sector, members of nearly all ethnic groups commonly discriminated in favor of other members of the same group. Some neighborhoods, particularly in slum areas of the capital, tended to be segregated ethnically, although interethnic marriage has become fairly common in urban areas.
There was frequent conflict, banditry, and cattle rustling among Somali, Turkana, Gabbra, Borana, Samburu, Rendille, and Pokot ethnic groups in arid regions located in North Eastern, Eastern, and Rift Valley provinces, which at times resulted in death. For example, during the year cattle rustling was rampant, and several persons were killed in Isiolo and Turkana in connection with cattle raids and counterattacks.
Between October 13 and 18, at least 14 persons were killed as a result of interethnic fighting in Isiolo over pasture and water. On October 14, seven persons were shot and killed in Tractor village, Ngaremara Division, in Isiolo. According to local media reports, the dead included two 12-year-old children, who were dragged out of their huts and shot as their parents watched. Insecurity in the region resulted in the closure of at least six schools. Several
teachers from the Borana, Somali, and Meru communities in Isiolo received death threats and were transferred. In response the government deployed hundreds of security officers to the area in pursuit of the attackers, but no arrests were made by year's end.
In response to armed incursions and kidnappings conducted from Somali territory, in October Kenyan military forces entered southern Somalia to conduct
operations against al Shabaab forces. In conjunction with these operations, the government launched internal security measures inside Kenya to counter suspected al Shabaab militants and sympathizers. Kenyan citizens, including Muslims and those of Somali ethnic origin, were generally supportive of these efforts; however, abuses occurred. For example, HRW reported that on November 11 , after an attack by suspected al-Shabaab militants in Garissa, security forces picked up people who looked Somali, beat them, and forced them to sit in dirty water while interrogating them. After an improvised explosive device exploded in the same area on December 12, police and soldiers rounded up and beat Kenyans of Somali origin over the next three days,
according to HRW. After grenade attacks occurred at a bus stop and bar in Nairobi in October, general public hostility against urban Somali refugees in Nairobi and Kenyans of Somali ethnic origin increased. The perception that Kenyan citizens of Somali origin were disproportionately successful in business contributed to public hostility.