Political marriage

A marriage of state in ancient use is a diplomatic marriage or union between two members of different nation-states or internally, between two power blocs, usually in authoritarian societies and is a practice which dates back into pre-history, as far back as early Grecian cultures in western society, and of similar antiquity in other civilizations. The fable of Helen of Troy may be the best known pre-historic tale reporting an incidence of surrendering a female member of a ruling line to gain peace or shore up alliances of state between nation-states headed by small oligarchies or acknowledged royalty.

While the contemporary Western ideal sees marriage as a unique bond between two people who are in love, families in which heredity is central to power or inheritance (such as royal families) often see marriage in a different light. There are often political or other non-romantic functions that must be served, and the relative wealth and power of the potential spouses should be considered. Marriage for political, economic, or diplomatic reasons was a pattern seen for centuries among European rulers.

Careful selection of a spouse was important to maintain the royal status of a family: depending on the law of the land in question, if a prince or king was to marry a commoner who had no royal blood, even if the first-born was acknowledged as a son of a sovereign, he might not be able to claim any of the royal status of his father. Throughout history, members of a royal family who are not granted a royal title rarely have much power.

Traditionally, many factors were important in the arranging of royal marriages. One such factor was the size of the tracts of land that the other royal family governed or controlled. Another, related factor was the stability of the control exerted over that territory: when there is territorial instability in a royal family, other royals will be less inclined to marry into that family. Another factor was political alliance: marriage was an important way to bind together royal families and "their countries during peace and war" and could justify many important political decisions.

Religion has always been closely tied to political affairs and continues to be today in many countries. Religious considerations were often important in marriages among royal families, particularly in lands where there was an established or official religion. When a royal family was prepared to negotiate or arrange the marriage of one of its children, it was extremely important to have a prospective spouse who followed the same religion or, at the very least, that the spouse be willing to convert before the wedding. In non-Catholic royal families, there were few things worse than marrying a person who was a Catholic. Some countries barred from accession to the throne any person who married a Catholic, as in the British Act of Settlement 1701. When a Protestant prince converted to Catholicism, he risked being disowned by his family, and often being barred from the throne himself. Some of these laws are still in force, centuries after the conclusion of Europe's Wars of Religion.

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