Factors that necessitated the adoption of Nigerian Federalism are as follows:
(i) Differences in ethnic Composition: There are differences in traditions, culture, language, religion, etc. These differences exist among the different ethnic groups, hence the adoption of federalism in Nigeria.
(ii) Fear of ethnic domination: The fear of one major ethnic group dominating others may give rise to the adoption of federalism.
(iii) Size of Country: Nigeria has a large population and with a wide geographical expression, federalism is a better option.
(iv) Minority interest: Adoption of federalism in Nigeria, is one way of protecting the interests of the minority. Nigeria has both the majority and minority tribes and other diversified interests and groups.
(v) Geographical Contiguity: The geographical nearness of the people in the country gave rise to the adoption of federalism.
(vi) Even development: Federalism promotes quick and even development and this is one of the reasons why Nigeria embraced it.
(vii) For security purposes: Different sovereign states may decide to come together by adopting federalism and this is done to have a secured sovereign state, for example, U.S. A., Switzerland, etc.
(viii) To generate Employment opportunities: Federal system makes for duplication of functions, thereby generating employment opportunities in the process.
(ix) Desire for a Union: There was the desire among the various groups to come together and form a union. This will remove all fears of external aggression.
(x) To bring government nearer to the people: Federalism may give rise to the creation of other units of government e.g states, local governments etc. This will help to bring the government nearer to the people.
(xi) Prevents inequalities : Federalism prevents inequalities among different groups. It removes the tendency of one or more groups becoming more powerful than the others.
(xii) Enhancement of the autonomy of States: This is only possible in federalism. In unitary state, autonomy is not granted component units e.g states, local governments.
(xiii) Expansion of Local Markets: Federalism creates the opportunity for the expansion of local markets.
(xiv) For effective administration: Duplication of functions which is allowed in a federal set up, makes for effective administration. This is because many people are involved in the administration of the country.