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Elsewhere I have defined noble law as “national legislation, or national or international customs, that regulate noble affairs. In many cases, this is not codified, but rather a set of rules and traditions that have gained acceptance” (see my book at http://www.findyournobleancestors.com).
Examples of some of the most important issues regulated by noble law are:
– claims to nobility (surname, coat of arms, title) by non-noble persons. This could, but must not, include: children with one or two noble parents but born out of wedlock; stepchildren of noble parents; children of a noble lady in an agnatic family, etc.
– claims of nobility of noble persons, when the claims cannot be automatically verified. This could be, for example, the inheritance of a noble title in a lesser line of the family when the greater line dies out.
– Borderline cases, such as those that were and were not among the old patrician families, to be counted among the nobility. Or the revival of a family’s peerage after some time of voluntary or involuntary loss of peerage (usually because one or all of the peerage qualities have not been used for two or more generations).
– the naturalization of the foreign nobility, that is, the assimilation of the immigrant nobility to the national nobility, generally with the purpose of assuring the foreign nobility the same privileges as the national one.
– Heraldry, and more specifically the use of certain symbols usually reserved for the nobility, such as crowns of noble rank, the use of sympathizers, etc. The order of arms, which is the appropriate combination of two or more coats of arms for marriage between two noble families, and similar issues may also be regulated.
In some countries the nobility is a subject of public law (Belgium, Finland, the Netherlands, and in Spain only with respect to titled nobility). In other countries this is not the case, and then the nobility may have organized into one or more associations in order to have an institution to deal with noble affairs such as those mentioned above. Therefore, it is of the utmost importance that each noble family define and clarify under which legislation, or under which set of rules or regulations, codified or not, they are subject.
Nobility law is a complex and multifaceted subject. Extensive research is often necessary to establish which rules apply to a specific noble family. A starting point may be to collect relevant literature from (or about) the country where the family is known (or believed) to have been ennobled (or first recognized as noble). This can be done by searching the many antique bookstores available on the Internet for keywords such as “nobility” or “nobility” in the title of the book. Sometimes a specific Internet site will be devoted to noble law (such as the Italian http://www.dirittonobiliare.com).
Perhaps the most important thing to remember about noble law is that it is not the same as public law. It may well be possible, according to national law, for a non-noble person to assume a noble surname, but this does not make them members of the nobility. A person can only be a member of the nobility if he is so according to noble law, whether or not it is in harmony with public law.