Answer by taking a quote from the following article:

The Turkana are a Nilotic people native to the Turkana District in northwest Kenya, a semi-arid climate region bordering Lake Turkana in the east, Pokot, Rendille and Samburu people to the south, Uganda to the west, and South Sudan and Ethiopia to the north. They refer to their land as Turkan. According to the 2009 Kenyan census, Turkana number 855,399, or 2.5% of the Kenyan population, making the Turkana the third largest Nilotic ethnic group in Kenya, after the Kalenjin and the Luo, slightly more numerous than the Maasai, and the tenth largest ethnicity in all of Kenya. Although this figure was initially controversial and rejected as too large by Planning Minister Wycliffe Oparanya, a court ruling (Feb 7, 2012) by Justice Mohammed Warsame (judge) stated that the Kenyan government accepts the 2009 census figures for Turkana.

The Turkana entered Turkana basin from the north as one unit of the Ateker confederation. This cluster split as a result of internal differences, leading to the emergence of distinct independent groups. The Turkana people emerged as a victorious group in the subsequent conflict, which led to enmity between the Turkana and other Ateker cluster groups, who formed military alliances against the Turkana. The Turkana emerged victorious again by co-opting young people from conquered groups. The military power and wealth of the Turkana increased in what is now the northern plains of Turkana.  The establishment of the Turkana people developed as a distinct group which expanded southwards conquering ethnic nations south of its borders. The Turkana people easily conquered groups it came in contact with by employing superior tactics of war, better weapons and military organization. By the 1600s, the Turkana basin had been fully occupied by the Turkana and their allies.  There was a relative long period of peace among indigenous ethnic communities around Turkana until the onset of European colonization of Africa. Sporadic conflicts involved Turkana fights against Arab, Swahili and Abyssinian slave raiders and ivory traders. European colonization brought a new dimension to conflict with Turkana putting up a lasting resistance to a complex enemy, the British. The Turkana put up and maintained active resistance to British colonial advances leading to a passive presence of colonial administration. By the outbreak of World War I, few parts of Turkana had been put under colonial administration.  From World War I through to the end of World War II, Turkana actively participated in the wars as allies of Britain against invading Italy. Turkana was used as the launching pad for the war against invading Italian forces leading to the liberation of Abyssinia.  After World War II, the British led disarmament and pacification campaigns in Turkana, leading to massive disruptions and dispossession of Turkana pastoralists. The colonial administration practiced a policy of deliberate segregation of Turkana people by categorizing Turkana Province as a closed district. This led to marginalization and underdevelopment in the lead up to Kenya's independence.

What is historical about the Turkana people?
The Turkana people easily conquered groups it came in contact with by employing superior tactics of war, better weapons and military organization.