Concept
Hereditary titles, in a general sense, are nobility titles, positions or styles that are hereditary and thus tend or are bound to remain in particular families. Though both monarchs and nobles usually inherit their titles, the mechanisms often differ, even in the same country. The British crown has been heritable by women since the medieval era (in the absence of brothers), while the vast majority of hereditary noble titles granted by British sovereigns are not heritable by daughters. Often a hereditary title is inherited only by the legitimate, eldest son of the original grantee or that son's male heir according to masculine primogeniture. In some countries and some families, titles descended to all children of the grantee equally, as well as to all of that grantee's remoter descendants, male and female. This practice was common in the Kalmar Union, and was frequently the case in the letters patent issued by King Eric of Pomerania, King Joseph Bonaparte conferred the title "Prince of Naples" and later "Prince of Spain" on his children and grandchildren in the male and female line. Historically, females have much less frequently been granted noble titles and, still more rarely, hereditary titles. However it was not uncommon for a female to inherit a noble title if she survived all kinsmen descended patrilineally from the original grantee or, in England and Iberia, if she survived just her own brothers and their descendants. Rarely, a noble title descends to the eldest child regardless of gender (although by law this has become the prevalent form of titular inheritance among the Spanish nobility). A title may occasionally be shared and thus multiplied, in the case of a single title, or divided when the family bears multiple titles. In the French nobility, often the children and other male-line descendants of a lawful noble titleholder self-assumed the same or a lower title of nobility; while not legal, such titles were generally tolerated at court during both the ancien regime and 19th century France as titres de courtoisie.