Religion has played and continues to play a crucial role in the making of the modern state of Nigeria. Based on a 2017 census from Afrobarometer, they found that 56% of inhabitants identified as Christian and 42% identified as Muslim with less than 5% identifying with other religions or none. This can even be seen in the breakdown of the geography of Nigeria. Although their are members of both religions spread out throughout the land, most Muslims live in the northern parts and most Christians can be found in the southern parts of the nation. This has been such a strong theme throughout the history that leaders have come to recognize the different identities of the citizens and planned policies and political campaigns around it. For example, the capital of Abuja was intentionally placed near the exact center of the nation even though that part of the nation is the least inhabitable being only dry desert. This not only symbolically shares the governmental powers between the two religions, but also gives easier access to every citizen and political leaders.
The use of religion also fills important gaps that the federal and local government does not have the resources for. These are usually general provisional benefits exclusive to the religious members. They each also provide to the benefit of the community through works of service or charity work. This can uphold a fragile social system and lack of resources such as food, water, electricity, construction, and other necessary actions to make society run smoothly. Also each of these religions emphasizes frugality and Muslims have the rule of zakat that requires them to give a certain portion of their income back to the community that they earned it from. These beliefs held and most importantly actions executed give Nigerian communities a leg up where the government falls short and is important to the running of society.
Religion in politics has also been present throughout the history and current political standing of the nation. A unique aspect of the Nigerian political aspect is that people tend to align with political leaders that share similar demographics to them rather than most other nations where people align with beliefs. This has caused many prominent parties to be followed and supported by one type of religion. This came to be a well understood fact to the point that the Nigerian constitution specifies that a president and vice president must be from opposing regions and subsequently different religions in order to be eligible to run and win an election. This just shows how ingrained in society the role of religion in and how even the constitution of the nation forces the coexistence of two religions in the same governing political party.
Overall, religion is synonymous with the culture and everyday life of Nigerians to the point of being completely intertwined with the government and running of the nation. Although it has been the root divide for many past and even less current problems, the population has put that difference aside through a couple decades of deliberation. Nigeria is superbly unique in this facet as almost no other nation has as big a population that is evenly split down the middle on religion that can make it work moderately well.
Sources:
https://www.chathamhouse.org/2021/03/collective-action-corruption-nigeria/context-religion-nigeria
https://news.gallup.com/poll/246689/nigerians-deeply-divided-religion-key-issues.aspx
https://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S1017-04992016000100003