The people of Dassanech live nearby the Ethio-Kenya and Ethio-Sudanese border. They share their boundaries with the Nyangatom in the northwest, Hamer in the north and east, the republic of Sudan in the west and Lake Turkana and Kenya in the south. They are also the East Cushitic Language Family, further they are the third populous ethnic group in south omo zone. Their livelihood mainly depends on livestock, cattle, goat, and sheep. And they also cultivate sorghum and maize in Omo delta, beside the common fishing practice.

The Dassanech or the Geleb has eight clans and many sub clans. Six of these clans believe to have migrated from Kismayu in Somalia. And the other two claims to have migrated from the northward Kenya. In the society there are several sorts of rituals associated to the level of age. But the famous one is the Dimi rite which deals that a girl transferred from childhood to adulthood. The relatives of the girls present different gifts, usually they prefer to offer bulls, then the women bring these gifts to the market to barter them with Shiforo( coffee husk). First they give some portion of the husk to the family and the remaining one boiled ceremonially for the community elders. Meantime the brothers and uncles of the girls slaughter ritual goats or sheep and the elders start to bless them for fertility and successful future life. Furthermore, the family and the elders give thanks to their gods or Waaq for allowing their daughters to survive to adult age and to become ready for marriage. But only six of the clans who claim to have originated from Kismayu practice this rite.