Early marriage is a global and ancient phenomenon; its frequency worldwide, but especially in Europe, has declined only in recent decades. Often, early marriage results from precarious situations of poverty, a lack of opportunities and education, and external threats, for example in refugee situations. However the concepts and perceptions of marriage, family, identities, and values in different societies are diverse, as the comparison of regulations and the practice of early marriage in over 40 jurisdictions shows. Even if early marriage appears generally undesirable, for some minors the alternatives are even worse. Some countries set fixed ages for marriage; others use flexible criteria such as physical or mental maturity to determine a threshold for marriage. All, however, until very recently provided for the possibility of dispensation. In Western countries, such dispensations have rarely been sought in the last decades and have consequently been abolished in some jurisdictions; elsewhere they still matter. Also, most countries bestow some legal effects to marriages entered into in violation of age requirements in the name of a favor matrimonii. Early marriage has an international dimension when married couples cross borders. Generally, private international law around the world treats marriages celebrated by foreigners in their country of origin as valid if they comply with the respective foreign law. Such application is subject to a case-specific public policy exception with regard to age requirements, provided the marriage has some relation to the forum. Recent reforms in some countries, Germany included, have replaced this flexible public policy exception with a strict extension of the lex fori to foreign marriages, holding them to the same requirements as domestic marriages and thereby disabling both a case-by-case analysis of interests and the subsequent remediation of a violation of the forum's age requirements. As a consequence, parties to a marriage celebrated abroad can be treated as unmarried, meaning they derive no rights and protection from their marriage, and their marriage may be limping - valid in one country, invalid in another. The extension of domestic age requirements to foreign marriage without exception, as done in German private international law, is problematic in view of both European and German constitutional law. The refusal to recognize early marriages celebrated abroad can violate the European freedom of movement. It can violate the right to marriage and family (Art. 6 Grundgesetz) and the child's best interests. It can violate acquired rights. It can also violate the right to equality (Art. 3 Grundgesetz) if no distinction is made between the protection of marriages validly entered into abroad and the prevention of marriages in Germany. Such violations may not be justifiable: The German rules are not always able to achieve their aims, not always necessary compared with milder measures existing in foreign laws, and not always proportional.
