nullity of marriage, in law, an unlawful marriage that is either void or voidable because of conditions existing at the time of the marriage. A bigamous or incestuous marriage, for example, is void, and there is no need to bring a suit to obtain a decree declaring it void. However, a decree is necessary to annul voidable marriages. Grounds, generally specified by statute, include fraud or duress preventing legal consent to the marriage and sexual impotence of one spouse that existed at the time the marriage was contracted and that was unknown to the other spouse. The results of nullity of marriage are different from those of divorce. A decree of nullity declares, in effect, that the parties never were married, and at one time it absolved them from all obligations to each other. Today, however, statutes in some states have mitigated the results of annulment, e.g., by making children of the void marriage legitimate and by permitting alimony. See husband and wife.

marriage, socially sanctioned union that reproduces the family. In all societies the choice of partners is generally guided by rules of exogamy (the obligation to marry outside a group); some societies also have rules of endogamy (the obligation to marry within a group). These rules may be prescriptive or, as in the case of the incest taboo, proscriptive; they generally apply to kinship groups such as clan or lineage; residential groups; and social groups such as the ethnic group, caste, or class.

Marriage is usually heterosexual and entails exclusive rights and duties of sexual performance, but there are instructive exceptions. For example, Nayar women of India would ritually marry men of a superior caste, have numerous lovers, and bear legitimate children. Among the Dahomey of West Africa, one woman could marry another; the first woman would be the legal "father" of the children (by other men) of the second. These examples highlight the functions of marriage to reproduce both a domestic division of labor and social relationships between different groups. Such functions are served even by the more common type of marriage, the union of one or more men with one or more women.

In most societies men and women are valued for their different roles in the household economy. Marriage therefore often occasions other economic exchanges. If a woman's labor is highly valued, a man may be required to offer valuable goods (bride-price) or his own labor (bride-service) to his wife's family. If a man's labor is more highly valued, the bride's family may offer goods (dowry) to the husband or his family.

Marriage as a Societal Bond

In many societies marriage links not just nuclear families but larger social formations as well. Some endogamous societies are divided into different exogamous groups (such as clans or lineages): Men form alliances through the exchange of women, and the social organization regulates these alliances through marriage rules. In some cases, two men from different groups exchange sisters for brides. Other instances involve an adult man marrying the young or infant daughter of another man; sexual relations would be deferred for many years, but the two men will have formed a strong bond. Marriages are often arranged by the families through the services of a matchmaker or go-between, and commence with a ritual celebration, or wedding. Some cultures practice trial marriage; the couple lives together before deciding whether they should marry. Society generally prescribes where newlywed couples should live: In patrilocal cultures, they live with or near the husband's family; in matrilocal ones, with or near the wife's family. Under neolocal residence, the couple establishes their own household.

Although marriage tends to be regarded in many places as a permanent tie, divorce is allowed in most modern societies. The causes of divorce vary, but adultery, desertion, infertility, failure to provide the necessities of life, mistreatment, and incompatibility are the most common. Civil unions are now permitted in Western countries, but for nearly a thousand years marriage in the Western world was a religious contract. The Christian church undertook its supervision in the 9th cent., when newlywed couples instituted the practice of coming to the church door to have their union blessed by the priest. Eventually the church regulated marriage through canon law. In contemporary N Europe marriage has lost some of importance, especially as social legislation has emphasized assuring equal financial benefits and legal standing to children born to unwed parents.

For the legal aspects of marriage, see husband and wife; consanguinity; divorce.

Forms of Marriage

Monogamy (the union of one wife to one husband) is the prevalent form almost everywhere. Polygyny (or polygamy; having several wives at one time), however, has been a prerogative in many societies (see harem). It is commonly found where the value of women's labor is high and may be practiced as a way of acquiring allies: A man may cement his bonds with several other men by marrying their sisters or daughters. Polyandry (having several husbands at one time) is rare, having occurred infrequently in Tibetan society, among the Marquesas of Polynesia, and among certain hill tribes in India. People who enjoy only a marginal subsistence may practice polyandry as a way of limiting births. It is also practiced where brothers must work together to sustain one household; they share one wife. The custom of marrying a widow to her late husband's brother is known as levirate marriage and was common among the ancient Hebrews. In sororate marriages a widower marries his deceased (or barren) wife's sister. The levirate and the sororate occur in societies where marriage is seen to create an alliance between groups; the deceased spouse's group has a duty to provide a new spouse to the widow or widower, thereby preserving the alliance. In recent years many gay-rights groups have sought official recognition of same-sex couples that would be comparable to marriage (see gay-rights movement).

common-law marriage: see under husband and wife.

annulment of marriage: see nullity of marriage.

Legal invalidation of a marriage. It announces the invalidity of a marriage that was void from its inception. It is to be distinguished from dissolution or divorce. To justify annulment, the marriage contract must have a defect (e.g., incompetence of one party because of age, insanity, or a preexisting marriage). Continued absence of one party may also justify annulment. Generally, annulment is easier if the marriage is unconsummated. Both secular law and Christian canon law have annulment procedures.

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Payment made by the groom or his kin to the kin of the wife in order to ratify the marriage. The practice is common in most parts of the globe in one form or another, but it is perhaps most prevalent in Africa. It is most often a matter of social and symbolic as well as economic reciprocity, being part of a long series of exchanges between the two intermarrying families. It represents a pledge that the wife will be well treated and serves as compensation for her family's loss. Payment may consist of goods or, less frequently, services, and it may be paid in one sum or regularly over a long period of time. See also dowry.

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Body of legal specifications and requirements and other laws that regulate the initiation, continuation, and validity of marriages. In western Europe most marriage law derives from Roman Catholic canon law. Although the church regards marriage as a sacred, indissoluble union, modern western European and U.S. marriage law treats it as a civil transaction. Marriage law allows only monogamous unions; partners must be above a certain age and not within prohibited degrees of blood relationship; and they must be free to marry and give consent to the marriage. Divorce is now almost universally allowed. Although Islamic law regards marriage as a contract between the two spouses for the “legalization of intercourse and the procreation of children,” it is also considered a gift from God or a kind of service to God; the Islamic practice of polygamy was always limited and has waned. Polygamous marriages are permitted under customary laws in many African countries, though there has been a growing trend toward monogamy. Marriage law in present-day China and Japan resembles that in the West. Although most jurisdictions restrict marriage to a union between a man and a woman, same-sex marriages have been legalized in The Netherlands, Belgium, Spain, and Canada. Civil unions or domestic partnerships between persons of the same sex, which entail many of the rights and obligations assumed by married couples, are recognized in numerous other jurisdictions, including several European countries and some U.S. states. Other U.S. jurisdictions, while not recognizing civil unions or domestic partnerships, grant a range of legal rights to same-sex couples.

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Legally and socially sanctioned union, usually between a man and a woman, that is regulated by laws, rules, customs, beliefs, and attitudes that prescribe the rights and duties of the partners and accords status to their offspring (if any). The universality of marriage is attributed to the many basic social and personal functions it performs, such as procreation, regulation of sexual behaviour, care of children and their education and socialization, regulation of lines of descent, division of labour between the sexes, economic production and consumption, and satisfaction of personal needs for social status, affection, and companionship. Until modern times marriage was rarely a matter of free choice, and it was rarely motivated by romantic love. In most eras and most societies, permissible marriage partners have been carefully regulated. In societies in which the extended family remains the basic unit, marriages are usually arranged by the family. The assumption is that love between the partners comes after marriage, and much thought is given to the socioeconomic advantages accruing to the larger family from the match. Some form of dowry or bridewealth is almost universal in societies that use arranged marriages. The rituals and ceremonies surrounding marriage are associated primarily with religion and fertility and validate the importance of marriage for the continuation of a family, clan, tribe, or society. In recent years the definition of marriage as a union between members of opposite sexes has been challenged, and in 2000 The Netherlands became the first country to legalize same-sex marriages. Seealso bridewealth; divorce; dowry; exogamy and endogamy; polygamy.

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Marriage that is without a civil or religious ceremony and is based on the parties' agreement to consider themselves married and usually also on their cohabitation for a period of time. Most jurisdictions no longer allow this type of marriage to be formed, though they may recognize such marriages formed before a certain date or formed in a jurisdiction that permits such marriages.

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