Somali society is based on a clan-family structure. The two major clan groups are the Samaal (or Samale) and the Saab (or Sab), named for two brothers who are said to have been members of the prophet Muhammad's tribe, the Quraysh of Arabia. Many Somalis believe that their ancestor from Old Testament times was Noah's son Ham.

Somali society is based on a clan-family structure. The two major clan groups are the Samaal (or Samale) and the Saab (or Sab), named for two brothers who are said to have been members of the prophet Muhammad's tribe, the Quraysh of Arabia. Many Somalis believe that their ancestor from Old Testament times was Noah's son Ham.

The Samaal, which make up about three-quarters of the Somali population, are divided into four main clan-families: the Dir, Daarood, Isaaq, and Hawiye. The Saab are divided into the Digil and Rahanwayn clan-families. Major clans can have thousands of members, each claiming descent from a common ancestor.

These clans are subdivided into subclans and into primary lineage groups. Somali men trace their membership in a particular clan-family through their patrilineage, going back a dozen or more generations. Clan groups with the longest ancestry have the most prestige. Clans and subclans are associated with the territory they occupy for most of the year.

The traditional political unit among the Somali people has been kinships. Dia-paying groups are groupings of a few small lineages, each consisting of a few hundred to a few thousand members. They trace their foundation to between four and eight generations.

Members are socially contracted to support each other in jural and political duties, including paying or receiving dia or blood compensation (mag in Somali). Compensation is obligatory in regards to actions committed by or against a dia-paying group, including blood-compensation in the event of damage, injury or death.