Sororal polygyny

Polygyny (/pəˈlɪdʒɪniː/; from Neoclassical Greek πολυγυνία from - poly- "many", and gyne "woman" or "wife") is the most common and accepted form of polygamy, entailing the marriage of a man with several women. Most countries that permit polygamy are Muslim-majority countries in which polygyny is the only form permitted. Polyandry is illegal in virtually every state of the world.

In some countries where polygamy is illegal, and sometimes even when legal, at times it is known for men to have one or more mistresses, whom they do not marry. The status of a mistress is not that of a wife, and any children born of such relationships were and some still are considered illegitimate and subject to legal disadvantage.

Today, polygyny is more widespread in Africa than in any other continent. Some scholars see the slave trade's impact on the male-to-female sex ratio as a key factor in the emergence and fortification of polygynous practices in regions of Africa. Generally in rural areas with growing populations, the higher the incidence of polygyny, the greater the delay of first marriage for young men. The higher the average polygyny rate, the greater the element of and social stratification.

Throughout the African polygyny belt stretching from Senegal in the west to Tanzania in the east, as many as a third to a half of married women are in polygynous unions, and polygyny is found especially in West Africa. Historically, polygyny was partly accepted in ancient Hebrew society, in classical China, and in sporadic traditional Native American, African and Polynesian cultures. In India it was known to have been practiced during ancient times. It was accepted in ancient Greece, until the Roman Empire and the Roman Catholic Church.

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