A morganatic marriage is a type of marriage that usually applies to people of unequal social rank. In certain countries, it is a contract marriage which prevents the passage of the husband's titles and privileges to the wife and any children born of the marriage.

Historically, in some European countries such as Germany, Great Britain, Spain, etc., the morganatic marriage is between a male from a royal or reigning house, and a woman with lesser status, being non-royal or within a non-reigning house. Sometimes a woman has a profession traditionally considered lower-status. Also various legal rights do not pass to her or her children. The children are nonetheless considered legitimate and all legal prohibitions against bigamy apply.

Morganatic marriage will exist when royalty or aristocracy choose a marriage partner who is not deemed appropriate and part of the society's nobility. Royal individuals are generally expected to follow standards as public figures in all aspects of how they live their lives including marriage. The personal desire to marry someone with whom they share romantic love is not a primary (fundamental) concern for getting married. When two people are not in social harmony and love is a key element, morganatic marriage can become the couple's solution.

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