Royal intermarriage

Royal intermarriage is the practice of members of ruling dynasties marrying into other reigning families. It was more commonly done in the past as part of strategic diplomacy for national interest. Although sometimes enforced by legal requirement on persons of royal birth, more often it has been a matter of political policy and/or tradition in monarchies.

In Europe, the practice was most prevalent from the medieval era until the outbreak of World War I, but evidence of intermarriage between royal dynasties in other parts of the world can be found as far back as the Late Bronze Age. Monarchs were often in pursuit of national and international aggrandisement on behalf of themselves and their dynasties, thus bonds of kinship tended to promote or restrain aggression. Marriage between dynasties could serve to initiate, reinforce or guarantee peace between nations. Alternatively, kinship by marriage could secure an alliance between two dynasties which sought to reduce the sense of threat from or to initiate aggression against the realm of a third dynasty. It could also enhance the prospect of territorial acquisition for a dynasty by procuring legal claim to a foreign throne, or portions of its realm (e.g., colonies), through inheritance from an heiress whenever a monarch failed to leave an undisputed male heir.

In parts of Europe, royalty continued to regularly marry into the families of their greatest vassals as late as the 16th century, thenceforth, tending to marry internationally. In other parts of the world royal intermarriage was less prevalent and the number of instances waxed and waned over time, depending on the culture and foreign policy of the era.

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) have often seen 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 may be considered. Marriage for political, economic, or diplomatic reasons, the marriage of state, was a pattern seen for centuries among European rulers.

At times, marriage between members of the same dynasty has been common in Central Africa.

In West Africa, the sons and daughters of Yoruba kings were traditionally given in marriage to their fellow royals as a matter of dynastic policy. Sometimes these marriages would involve members of other tribes. Erinwinde of Benin, for example, was taken as a wife by the Oba Oranyan of Oyo during his time as governor of Benin. Their son Eweka went on to give birth to the dynasty that rules the Kingdom of Benin today.

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