The Great Rift has always been a migratory route into and out of Africa. Even as the birds of Europe that summer in the southern hemisphere use its sheer walls as a guiding line and its numerous lakes as places to stop and rest and replenish energy, so, over the millennia, herds of animals and human tribes have passed this way using the same steep walls for refuge and the lake shores for temporary encampments. The earliest humans to use the Great Rift highway were hunter-gatherers following the wild game that roamed the valley floor in their millions; --- for this was an age before the drying out of the land, an age when even the great Sahara was a land of plenty. Their bones, with those of numerous animals, some of gigantic size, are found throughout the Rift, but most notably at the level of the ancient lake shores of Baringo and Turkana.

Much later, into recent times, it has been the pastoral peoples of Africa, herding their camels, cows and sheep from watering point to watering point in the ceaseless quest for grazing, who have adopted the valley and its steep sides as their milieu. One such group, close relations of Maasai and fellow maa-speakers, were the Samburu.  Somehow an offshoot group of the Samburu settled and thrived on the shores and islands of Lake Baringo; they are the Ilchamus, sometimes refered to as Njemps.
The Ilchamus are not actually pastoralists at all; though they might yearn to be and still retain many of the customs and traditions associated with cattle-people. In the distant past they lost their herds of cows to theft or disease and had to completely change their life-style to fishing and cultivation, using simple irrigation. This was truly revolutionary because the eating of fish was taboo with the Maasai, Samburu and most other tribes. When the early European explorers such as Thomson and Teleki passed through Baringo in the 1880s, it was the Ilchamus that fed them and re-stocked their expeditions. Later, the irrigation methods were abandoned ---- only to be revived in the 1940s. These friendly people, innovative as ever, are trying to develop tourism as an alternative source of income and will probably succeed as long as the Lake does not dry up.

The Tugen people (or Kamasia)  inhabit the valley lands to the south of Baringo, the Tugen Hills and the eastern side of the Kerio river in the Kerio Valley. They were traditionally pastoralists but have found it difficult to maintain the pastoral way of life due to a self-perpetuating cycle of events involving high temperatures, low rainfall and seasonal lack of grazing in the valleys, and seasonal herding of animals into the hills where rainfall is high but the soils thin and rocky and vulnerable to erosion. They are now placing more emphasis on agriculture, terracing in the hills and restricting sheep and goats to the lowlands. However, no true Tugen can forget his heritage. Every family has at least a few cows in the homestead or in a not-too-distant field, as milk is an important part of the diet. Bride-price or dowry is still negotiated in terms of cattle.
The Tugens have produced some notable athletes; undoubtedly Paul Tergat, the marathoner, is the most famous of them all.