A segmentary lineage society of about a million people astride the middle Benue, with no chiefs at all: every Tiv traces descent from a single ancestor through Ichongo or Ipusu, and authority sat with lineage elders, the 'Orya'. An expanding farming people who spread north from the Benue toward the Jos Plateau - and precisely the sort of large, chiefless nation the atlas has been leaving blank.
Not an ending: British forces entered Tivland in 1906 and the southern districts in 1911, and indirect rule failed badly against a society with no kings. The Tiv envelope hands over to the Protectorate of Northern Nigeria and Colonial Nigeria at 1900; over eight million Tiv speakers live in Benue and neighbouring states today.
The Ethnographic Survey volume by the anthropologists who defined Tiv segmentary organisation and land tenure - polity-specific.
Companion survey placing the Tiv among their Benue-valley neighbours (Jukun, Idoma, Igala).