The Niger -Volta branch of the Niger-Congo family of African languages which includes All west central eastern African languages except the Afro Asiatic languages like Hausa, Somali, Berber, Ethiopiclanguages and Arabic. Fulani is a Niger Congo African language too. The Niger-Volta languages are spoken mainly in Nigeria, Benin, Togo and Volta region of Ghana. They include principally Yoruba, Igbo, Nupe, Ebirra, Urhobo-Isoko, Edo Itsekiri, Igala, Idoma, Gwari, some Ijaw dialects, Egun, Fọn and Ewe. This is the largest linguistic group in Nigeria with about 55% of the population speaking Niger Volta languages natively. Hausa and Longuda are both Afro Asiatic languages and the second largest linguistic group in Nigeria by native speakers. The third group are the Bantu and semi-,Bantu speakers like the Efik, ibibio, Kalabari, Ekoi, Tiv, Chamba, Birom and Mumuye, these people were once widespread in Nigeria but were displaced about 3000 years ago by Niger-Volta speakers and most bantus migrated out through Cameroon into central, Eastern and southern Africa making the Ndebele and Shona of Zimbabwe
Luba of the DR Congo
Zulu, South Africa
Sukuma, Tanzania
Kikuyu, Kenya . Amongst others
The Kanuris of north Eastern Nigeria speak a Nilotic language related to Songhai and the languages of the Sudan, Kenya and Uganda such as Luo and Masai. The Ashanti and other Akan people speak the Kwa branch or Western Niger Volta languages spoken in Togo, Ghana and the Ivory Coast. The Ga of Accra speak a Niger Volta language similar to Nigerian.

Yoruba and Igbo are sub divided into Yoruboid and Igboid branches of Niger-Volta. But people spoke one language which separaed into two different languages about 2,000 to 2500 years ago. The closest living language to Yoruba today is Itsekiri which shares 72% of its vocabulary with standard Oyo/Lagos yoruba and up to 88% of its vocabulary with South-Eastern Yoruba dialects like Ilaje, Ikale and Owo. Itsekiri is very likely a surviving remnant of the oldest continuously spoken form of Yoruba. Igala is the other language similar to Yoruba and shares 60% of its vocabulary with both Yoruba and Itsekiri.

Igbo belongs to the Igboid group and has been influenced by igala and Idoma in Northern Igboland and by Effik, Ibibio and Ijaw in the south East and by Edo in the West. It's closest relative is still Yoruba with which it's shares similar grammatical structure and many cognate words. Urhobo, Isoko, some Ijaw dialects Esan, Bini and other Edo dialects belong to the Edoid branch of the Niger Volta family. They are transitional languages that separated Yoruba from Igbo. Nupe, Ebirra and Gwari belong to the northern branch known as Nupoid languages. Igbo is also related to Urhobo and Edo too and you will find elements of the same words across all these languages. Egun spoken in Badagry is the oldest aboriginal Niger Volta language spoken in Nigeria. It used to be spoken across most of Western Nigeria and it's speakers were gradually absorbed by incoming Yoruba groups. Egun has contributed significantly to the phonology (sound of modern Yoruba) and it's underlying vocabulary. Egun is a dialect of Fon or Dahomey spoken in the Republic of Benin and Togo. Many Yoruba groups live in Togo and Benin too.

All Nigerians except the Fulani also share a common DNA gene pool, so the Hausa might by accident have adopted an Afro Asiatic trade language but he might once have spoken a language similar to Yoruba and Igbo thousands of years ago before they switched languages.

Nigerian Cultures and languages