The region through which the lower riches of the Omo River flows is extremely complex.
It consists of a mosaic of different ecological zones, each with their own characteristics.
It is inhabited by different peoples who speak Nilotic, Cushitic, Surmic and Omotic languages.
Although the entire course of the Omo river is in which north west Kenya and south Sudan also play a role. The recent history of the region and especially where the Omo people come from and how they evolved is also important.
The Omo Valley
The Omo River is 760km long, originating in the high shewan highlands in Ethiopia and crossing the fertile and hilly regions of Kaffa. The upper riches are characterized by ravines, waterfalls and rapids. The river’s total vertical drop is 2000 meters and the greatest height difference occurs in its upper reaches.
The river becomes wider and calmer to the east of the town of Maji, where it reaches the lowlands. In its south west course the Omo crosses the barren lowlands until it finally flows into Lake Turkana, 375 meters above sea level.
The Omo has many tributaries of which the Mago is one of the most important, branching off the Omo shortly before Lake Turkana. The area to the west of the Omo is dominated by the Kibish Valley. The seasonal Kibish river is dry almost year all round.; water flows only at the peak of the rainy season.
There are mountain ranges to the east of the lower Omo River from which smaller rivers supply the Omo during the rainy season. The Omo is the region’s only year round water course, which makes it the lifeblood of these barren lowlands.
The Omo banks are fertile because the river breaks its banks annually in August and September and floods entire regions. When the water retreats there is enough moisture in the soil to plant and produce a harvest which is guaranteed unless subsequent heavy rains in the highlands make the river burst its banks again and wash away the fields.
In many places the Omo river banks are covered in gallery forests. These are relatively dense strips of woodland that offer good protection to man and animals against scorching heat.
The lower Omo region is relatively small, approximately 26000 km2. It is the homeland of the Hamer, Beshada, Banna, Kara, Kwegu, Nyangatom, Dassanach, Mursi, Suri and Bodi, approximately 110,000 people in total.
The region is characterized by a distinct form of inter-group acculturation in which dominating group have greatly influenced and still influence their neighbors both culturally and sometimes linguistically and where disputes over pasture may cause serious conflicts, sometimes resulting in the loss of annexation of important areas.
The ethno history of Omo valley peoples has not yet been studied in detail. Some anthropologists have published fragments on individual tribes.
But a general coordinated study in which the history of the different tribes is combined is lacking. Some studies of related peoples in Kenya and Uganda indicate that the cultural identity of the entire region’s herding tribes as we now know them is the result of a protracted process of migrations and changing inter-group relations.
Driven out by stronger enemies or searching for more suitable territory , the Nilotic, Cushitic, surmic and Omotic speaking groups moved through the region for decades. During this process major shifts occurred.
The territory of some groups was occupied by stronger neighboring peoples, resulting in the survivors having to leave their territory or be absorbed into the occupier’s group. In other cases small groups merged and formed a new people.
