Under civil law, Nigeria does not recognize polygamous unions. However, 12 out of the 36 Nigerian states recognize polygamous marriages as being equivalent to monogamous marriages. All twelve states are governed by Sharia law. The states, which are all northern, include the states of Bauchi, Borno, Gombe, Jigawa, Kaduna, Kano, Katsina, Kebbi, Niger, Sokoto, Yobe, and Zamfara, which allow men to take more than one wife.

Nigeria is part of the "polygamy belt", a region in West Africa and Central Africa where polygamy is common and deeply rooted in the culture. Nigeria is estimated to have the fifth highest polygamy prevalence in the world, with 28% of the population living in polygamous marriages, with only four countries (Burkina Faso, Mali, Gambia and Niger) having a higher prevalence.

Legality Zamfara State was the first to legislate polygamy, which occurred on January 7, 2000. Gombe State has been the most recent state to provide for civil polygamy, legalizing it on December 14, 2001.

As the southern region of Nigeria is predominantly Christian, polygamous marriages have not been legally introduced at this time. Attempts to introduce Sharia (thereby legalizing polygamy) have been made in Oyo State, Kwara State, Lagos State, and several others, but all have been unsuccessful. Polygamous unions are recognized by customary law in Nigeria, providing a handful of benefits for those in polygamous unions ranging from inheritance rights to child custody.

As of 2009, there has yet to be any debate of introducing a measure that would allow for civil polygamous marriages to be recognized nationwide, rather than allowing legislation to remain on a state-by-state basis. There are an estimated forty million polygamists in Nigeria.

Dynamics There are no requirements based on religion in the North, therefore Christians are legally allowed to form polygamous unions just as Muslims may do. Christian church leaders such as Archbishop Peter Akinola of the Anglican Church of Nigeria have condemned the practice of polygamy by Christians, with Akinola going on to write "The observation [of polygamy] will destroy our witness if not firmly addressed. We cannot claim to be a Bible-believing church and yet be selective in our obedience." Reports of Nigerian Mormons practicing polygamy have also surfaced.

Despite the four-wife limitation, there have been numerous indications that many Nigerians bypass this law, such as with Muhammadu Bello Masaba, an 84-year-old Islamic cleric who was accused of illegal marriage due to his exceeding number of spouses, in which he had 86 wives. The charges were later withdrawn by the Niger State Sharia commission, with Masaba able to retain all of his spouses.

On an opposite note, it was reported in April 2007 that a Nigerian lesbian, Aunty Maiduguri, married four women in an elaborate ceremony in Kano State, though her union is not recognized by the government, and Maiduguri and her partners were forced to go into hiding shortly after the ceremony to avoid the possible threat of being stoned if convicted for lesbianism, which results in capital punishment for married Muslim women or caning for single Muslim women in Nigerian areas under Sharia law.

Effects on children In most polygamous households, parents have little time and money to devote to their children. Therefore, children from these homes beg on the streets to meet their basic requirements, including food, clothes, and shelter. Research in Gombe in 2017 found that children from monogamous families are happier than their counterparts in polygamous families. This accounted for 75.9% of the total responses. The daughters of poor parents are most neglected since neither formal nor Islamic kinds of education are given to them. Most of them end up being married off at age 12 and become teen mothers with negative health effects.Batare, Andrew Lothan. ,2024. "An Investigation into the Media Representation of the Almajiri System in Bauchi State, Nigeria." Order No. 31868977, University of Salford (United Kingdom).

States where polygamy is legally recognized Bauchi Bauchi State has been the most recent Nigerian state to legislate civil recognition of polygamous marriages for its citizens, which was established after the implanting of Islamic Sharia law on July 1, 2001. Polygamy among the impoverished make up a large portion of the population in Bauchi State. Polygamous unions and the large households they create contribute significantly more to child poverty than smaller monogamous households. Though polygamy and early marriages are customary, they have raised fertility rates and brought about increased poverty and insecurity. The increased fertility rates brought about by the legalisation of polygamy have overwhelmed already lacking resources. As families do not have the resources to educate their childrenEmeka, C. (2020). The Causes of Poverty in Northern Nigeria. CAN Conference, Gombe. An Unpublished Paper., especially girls, these girls are married young, usually around age 12. This then fosters a cycle in which girls get married and have children young that cannot be provided for, then the daughters of those girls get sent off to get married and have children young, thus perpetuating a cycle of povertyBatare, Andrew Lothan. (26-29),2024. "An Investigation into the Media Representation of the Almajiri System in Bauchi State, Nigeria." Order No. 31868977, University of Salford (United Kingdom)..

Borno Polygamy is regularly practiced in Borno State as one of the states in which it is legally permissible. It is also believed that monogamous marriages as a norm is a colonial concept, and by participating in polygamous unions, husbands and wives are battling that concept Usman, H. B. (1989). The consequences of family breakdown in post-independence Nigeria: a case study of Borno state (Doctoral dissertation, University of Warwick)..

Gombe Polygyny is permitted under Islamic law in Gombe, with the objective of sustaining proper social order and wellbeing in the community. However, despite Islamic law permitting up to four wives, a survey taken in Gombe in 2017 showed that the majority of men limited themselves to two wives.

Despite the fact that 83% of the surveyors were married in polygynous families, only 11.6% of the men had a third wife and 3.6% of the men had a fourth. Additionally, only 13.4% of the wives agreed that their husbands treated all wives equally, which contradicts Islamic law. Moreover, 47.2% of co-wives stated remained cordial with other co-wives, citing favoritism by the husband as the source of disagreementsIsah, A. B. (2017). The Communal Challenges of Polygyny on Women and Children in Gombe Metropolis: A Socio-Islamic Viewpoint..

Jigawa Jigawa state is governed by Sharia law, which allows a man to have more than one wife. The 2018 DHS found that 44.7% of women in Jigawa state were in polygamous unionsSalako, Julius, Damola Bakare, Tim Colbourn, Adamu Isah, Osebi Adams, Funmilayo Shittu, Obioma Uchendu, et al. “Maternal Mental Well-being and Recent Child illnesses–A Cross-sectional Survey Analysis From Jigawa State, Nigeria.” PLOS Global Public Health 3, no. 3 (March 2, 2023): e0001462. https://doi.org/10.1371/journal.pgph.0001462..

Kaduna Polygamous marriage is a prevalent social structure in Kaduna state. A survey taken in Zaria, Kaduna in 2024 shows that communication and quality time are important to preserving a healthy relationship. They also stated that “Making joint decisions through open and respectful communication.” is important in a marriage, which may contradict other viewpoints of men as sole decision-makes. However, a large portion of conflict that takes place comes from financial constraints, with the majority of participants agreeing that their partner is not completely transparent about family finances, and how conflict can arise if spouses and children are not taken care of.

Kano A large reason for polygamy in Kano has to do with a preference for the number or sex of children. Even though the woman does not necessarily have biological input on that, a man my take another wife in hopes that she would birth a child of a different sex. In a 2017 surveyLambu, I. B. (2017): An analysis of widowhood and orphancy in some part of Kano state, Dutse journal of pure and applied Sciences (DUJPAS), Federal University Dutse it was found that wives show a 20% higher preference for having sons than their husbands, as providing male children may lead to more marital securityLambu, I.B., Ahmed, B.Y. (2018) Some Cultural Dilemmas to Family Planning Decisions in Kano Metropolis, Kano State, Nigeria, Dutse journal of pure and applied Sciences (DUJPAS), Federal University Dutse.

Katsina In focus group discussions taken place in Katsina in 2011, it was found that husbands tend to split their days with co-wives evenly. However, the wives may negotiate different days between each other depending on their ovulation periodsUjuju, C., Anyanti, J., Adebayo, S.B., Muhammad, F., Oluigbo, O. and Gofwan, A. (2011), Religion, culture and male involvement in the use of the Standard Days Method: evidence from Enugu and Katsina states of Nigeria*. International Nursing Review, 58: 484-490. https://doi.org/10.1111/j.1466-7657.2011.00900.x. Consequently, in a 2019 survey on marital jealousy in Hausa Muslim women in Katsina, 26% of the respondents classed their jealousy levels as high (20%) or very high (6%). 37% of the respondents stated that their reason for jealousy was sharing a husband, and 15% of the respondents admitted to checking their husband’s phone. This is usually due to the fact that the husband spends two days each with each wife. The first wife loses the monopoly on days that she previously had, leading to jealousyLadan, Suleiman. (2019). Understanding marital jealousy among Hausa Muslim women of northern Nigeria. .

Kebbi Just post independence, a third of males reported being in a polygamous marriage and 54-60% of women reported being in polygamous unions. Marriage order was relevant, but only particularly in unions with 3-4 wives. Additionally, during this time, divorce was frequent so a woman’s position in the marriage was constantly changing. However, in a 2021 survey of female homestead farmers 62.5% of respondents reported living in households of 6-10 people and 20.8% reported living in households of 11-15 people. Most of the respondents were from polygamous households in rural areas, created in order to increase farming labourAngo Adamu Kamba, Ebenihi Ojomugbokenyode, Tambari Ismaila Waziri, Ahmad Nabila. Socio-economic Evaluation of Women Homestead Farmers in Zuru Emirate, Kebbi State, Nigeria. International Journal of Applied Agricultural Sciences.  Vol. 7, No. 2, 2021, pp. 84-88. doi: 10.11648/j.ijaas.20210702.12.

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