information:extraction
Rank within the nobility

Nobility might be either inherited or conferred by a fons honorum. It is usually an acknowledged preeminence that is hereditary, i.e. the status descends exclusively to some or all of the legitimate, and usually male-line, descendants of a nobleman. In this respect, the nobility as a class has always been much more extensive than the primogeniture -based titled nobility, which included peerages in France and in the United Kingdom, grandezas in Portugal and Spain, and some noble titles in Belgium, Italy, the Netherlands, Prussia, and Scandinavia. In Russia, Scandinavia and non-Prussian Germany, titles usually descended to all male-line descendants of the original titleholder, including females. In Spain, noble titles are now equally heritable by females and males alike. Noble estates, on the other hand, gradually came to descend by primogeniture in much of western Europe aside from Germany. In Eastern Europe, by contrast, with the exception of a few Hungarian estates, they usually descended to all sons or even all children.

In France, some wealthy bourgeois, most particularly the members of the various parlements, were ennobled by the king, constituting the noblesse de robe. The old nobility of landed or knightly origin, the noblesse d'épée, increasingly resented the influence and pretensions of this parvenu nobility. In the last years of the ancien régime the old nobility pushed for restrictions of certain offices and orders of chivalry to noblemen who could demonstrate that their lineage had extended " quarterings ", i.e. several generations of noble ancestry, to be eligible for offices and favours at court along with nobles of medieval descent, although historians such as William Doyle have disputed this so-called "Aristocratic Reaction". Various court and military positions were reserved by tradition for nobles who could "prove" an ancestry of at least seize quartiers (16 quarterings), indicating exclusively noble descent (as displayed, ideally, in the family's coat of arms) extending back five generations (all 16 great-great-grandparents).

This illustrates the traditional link in many countries between heraldry and nobility; in those countries where heraldry is used, nobles have almost always been armigerous, and have used heraldry to demonstrate their ancestry and family history. However, heraldry has never been restricted to the noble classes in most countries, and being armigerous does not necessarily demonstrate nobility. Scotland, however, is an exception. In a number of recent cases in Scotland the Lord Lyon King of Arms has controversially (vis-à-vis Scotland's Salic law) granted the arms and allocated the chiefships of medieval noble families to female-line descendants of lords, even when they were not of noble lineage in the male line, while persons of legitimate male-line descent may still survive (e.g. the modern Chiefs of Clan MacLeod).

In some nations, hereditary titles, as distinct from noble rank, were not always recognised in law, e.g., Poland's Szlachta. European ranks of nobility lower than baron or its equivalent, are commonly referred to as the petty nobility, although baronets of the British Isles are deemed titled gentry. Most nations traditionally had an untitled lower nobility in addition to titled nobles. An example is the landed gentry of the British Isles. Unlike England's gentry, the Junkers of Germany, the noblesse de robe of France, the hidalgos of Spain and the nobili of Italy were explicitly acknowledged by the monarchs of those countries as members of the nobility, although untitled. In Scandinavia, the Benelux nations and Spain there are still untitled as well as titled families recognised in law as noble.

In Hungary members of the nobility always theoretically enjoyed the same rights. In practice, however, a noble family's financial assets largely defined its significance. Medieval Hungary's concept of nobility originated in the notion that nobles were "free men", eligible to own land. This basic standard explains why the noble population was relatively large, although the economic status of its members varied widely. Untitled nobles were not infrequently wealthier than titled families, while considerable differences in wealth were also to be found within the titled nobility. The custom of granting titles was introduced to Hungary in the 16th century by the House of Habsburg. Historically, once nobility was granted, if a nobleman served the monarch well he might obtain the title of baron, and might later be elevated to the rank of count. As in other countries of post-medieval central Europe, hereditary titles were not attached to a particular land or estate but to the noble family itself, so that all patrilineal descendants shared a title of baron or count (cf. peerage). Neither nobility nor titles could be transmitted through women.

Some con artists sell fake titles of nobility, often with impressive-looking documentation. This may be illegal, depending on local law. They are more often illegal in countries that actually have nobilities, such as European monarchies. In the United States, such commerce may constitute actionable fraud rather than criminal usurpation of an exclusive right to use of any given title by an established class.