Social groups
The Keiyo dialect has four predominant subdialects. These are Irong, Mutei, Marichor and Metkei.
Territorially, the Elgeiyo People divided their land into 21 east-west stretches to control intermarriage and displacement of a clan by other clans and a system of totems was acquired. The land was divided so that each group had access to the banks of Kerio River and thus the totems ran perpendicular to the river. From the south to the north the clans are Metkei, Kapkwoni, Maoi, Tumeiyo, Kowochi, Mwen,Choop, Morop, Samich, Kapsiro, Kenenei Kipking'wo, Sego, Epke, Chang'ach, Rokocho, Mutei, Maam, Irong', Kaptany, and Kapchemutwa.[4] The land was sub-divided to members of the same clan marked by a series of stones referred to as Koiwek.
Age-set (Ebenda)
The Elgeiyo social organization centers on the age set, or ebendo. There are eight age-sets (ebenwek) which are rotational, meaning after the end of one age set (after approximately 120 years), a new age set begins. Unlike the Nandi and the Tugen, who have only seven age sets (due to loss of an entire age set in battle), the Keiyo retained eight. The order is given below. Ebendo was given out during initiation. The age set system is organized in such a way that a father and a son cannot be of the same or sequential age sets. That is, there must be one ebendo between a father and a son. For example, a Kipkoimet cannot beget a Kaplelach. The Elgeiyo do not consider a woman to have an age set. Hence, she can marry any age set except that in which her father belongs. The age sets are:
- Maina
- Chumo
- Sawe
- Korongoro
- Kipkoimet
- Kaplelach
- Kipnyigei
- Nyongi
A member of an age set for example kipyigei, identifies himself in Keiyo as "A'ii Kipyigei", meaning he is of Kipnyigei age-set. On the other hand, a married woman identifies herself using the age-set of her husband. For example, a woman married to a kipnyigei will identify herself as "Aabo Kipyigeii", meaning she is of a kipyigeei.