Concubines

Concubinage is an interpersonal relationship in which a person engages in an ongoing sexual relationship with another person to whom they are not or cannot be married to the full extent of the local meaning of marriage. The inability to marry may be due to multiple factors such as differences in social rank status, an existing marriage, religious prohibitions, professional ones (for example Roman soldiers) or a lack of recognition by appropriate authorities. The woman in such a relationship is referred to as a concubine.

The prevalence of concubinage and the status of rights and expectations of a concubine have varied between cultures as well as the rights of children of a concubine. Whatever the status and rights of the concubine, they were always inferior to those of the wife, and typically neither she nor her children had rights of inheritance. Historically, concubinage was frequently entered into voluntarily (by the woman or her family) as it provided a measure of economic security for the woman involved. Involuntary or servile concubinage sometimes involved sexual slavery of one member of the relationship, usually the woman. Unlike ancient cultures, Christian Europe opposed concubinage, regarding any sexual relations outside of a monogamous marriage as sinful. Nevertheless, sexual relations outside marriage were not uncommon, especially among royalty and nobility, and the woman in such relationships was commonly described as a mistress. However, the children of such relationships were counted as illegitimate and were barred from inheriting the father's title or estates, even when there was an absence of any legitimate heirs.

While various forms of long-term sexual relationships and co-habitation short of marriage have become increasingly common in the Western world, these are generally not described as concubinage. The terms concubinage and concubine are used today primarily when referring to non-marital partnerships of earlier eras. In modern usage, a non-marital domestic relationship is commonly referred to as co-habitation (or similar terms), and the woman in such a relationship is generally referred to as a girlfriend, lover or (life) partner.

Concubinage was highly popular before early 20th century all over Asia. The main function of concubinage was producing additional heirs, as well as bring males pleasure. Children of concubines had lower rights in account to inheritance, which was regulated by Dishu system.

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