[1] The region had the third-, fourth- and fifth-largest indigenous ethnic groups including Igbo, Ibibio and Ijaw.

The eastern boundary lies between the border of Nigeria and Cameroon and the southern coast is along the Gulf of Guinea.

Obudu Plateau in the northeastern area, the Oban and Ikom Hills along the eastern boundary with Cameroon were a few of the highlands in the region.

[5] In 1849, John Beecroft, the governor of Fernando Po became the British consul agent for the Bights of Benin and Biafra.

[6] Beecroft was chosen to be in charge of regulating the trade at the ports of old and New Calabar and those at Benin, Bonny, Bimbia and the Cameroons between the residents and British merchant firms.

[13] In many areas in the region, the use of native courts to settle debts and bride price were important social institutions.

[17] The traditional society of the Igbos was democratic and individualistic with titles, wealth and age being the primary determinants of prestige.

During colonial rule, the Igbos spread to other regions of British West Africa, first working as traders and laborers and then establishing small scale businesses in Lagos and other urban districts.

During pre-colonial and colonial rule, the Efiks controlled trading post up the Cross River to the Ports of Calabar.

The other ethnic groups of the Niger Delta system include the Ijaw speaking people of Opobo, Bonny, Degema, Okrika, Buguma, Brass and Abonnema.

Other groups within the region were the Annang of Ikot Ekpene, Yakurr, Bahumono, Oron, Ogoni and Ekoi.

In the 1960s, the government promoted rubber, cocoa and palm grove schemes to increase the output of cash crops.

The government also established farm settlements at Ohaji, Igbariam, Boki, Ulonna, Erei, Uzo-Uwani and Egbema to encourage agriculture.

The Eastern Nigeria Marketing Board came into effect in 1954 and was given the responsibility to manage the region's cash or export crops.

Part of the initiative of the community development ministry was the clearing of land for passable laterite and earth roads.

In the southern parts of region where tidal waterways and swamps dominate the vegetation, barges and river craft are used for transportation.

The Nigerian railway line in the region runs through Enugu, Umuahia, Aba and Port Harcourt.

The region like Nigeria during the first republic operated a parliamentary system of government with a premier leading the executive branch and a bicameral legislature.

There were three tiers of governance levels within the system, the county and urban districts, the municipalities and the local councils.

[32] An African dominated government institution, the Eastern Regional Assembly with the powers to debate but not enact laws was established in 1948.

But after the Aba riot of 1929, the system gradually gave way to the Native Authority administration led by older men within the communities.

[38][39] Half of the money was used as subvention given to agencies managing the schools and to ensure a universal primary education programme.