House law

House law or House laws (Hausgesetze) are rules that govern a royal family or dynasty in matters of eligibility for succession to a throne, membership in a dynasty, exercise of a regency, or entitlement to dynastic rank, titles and styles. Prevalent in European monarchies during the nineteenth century, few countries have house laws any longer, so that they are, as a category of law, of more historical than current significance. If applied today, house laws are mostly upheld by members of royal and princely families as a matter of tradition.

Some dynasties have codified house laws, which then form a distinct section of the laws of the realm, e.g., Monaco, Japan, Liechtenstein and, formerly, most of Germany's monarchies, as well as Austria and Russia. Other monarchies had few laws regulating royal life. In still others, whatever laws existed were not gathered in any particular section of the nation's laws. In Germany where many dynasties reigned as more or less independent sovereigns, laws governing dynastic rights constituted a distinct branch of jurisprudence called private princely law (Privatfürstenrecht).

In some cases, house laws are rules or traditions that are treated as if they have the force of law. In the United Kingdom an example of this might be considered the custom whereby a wife shares in her husband's hereditary titles and rank. While this is settled common law with respect to the wives of peers and commoners, it is less clear when it comes to consorts of the king and princes. When, in 1923, Prince Albert, Duke of York became the first male member of the British royal family to marry a non-princess in more than 300 years (with the sovereign's approval), so an announcement was apparently issued by Buckingham Palace and carried in the London Gazette and The Times, "It is officially announced that, in accordance with the settled general rule that a wife takes the status of her husband, Lady Elizabeth Bowes-Lyon on her marriage has become Her Royal Highness the Duchess of York, with the status of a Princess".

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