Historical background and the two main notions of princehood

The Latin word Princeps, kin to "primus" and "first among equals", was established as the title of the more or less informal leader of the senate some centuries BC. Emperor Augustus established the formal position of monarch on basis of principate, not dominion. He also tasked his grandsons as summer rulers of the city when most of the government were on holiday in country or attending religious rituals, and for that task, granted the title Princeps.

Abstract notion

The original but least common use is as a generic (descriptive, not formal) term, one originating in the application of the Latin term princeps (i.e. the Emperor, or generalized: ruler) from Roman (actually Byzantine) law and classical "ideology" to the European feudal society. In this sense, it can in principle be used for any ruling (hereditary or elective) monarch, regardless of his title and protocolary rank.

Genealogical Princes, by birth or equivalent

A Prince of the Blood is a male member of a ruling house (imperial or royal family et cetera). In some monarchies, however, this appellation is a title in its own right, of more restricted use; for instance, as in the French Prince du Sang, restricted to paternal royal descendants. Depending on national tradition, the appellation may have restricted scope, often no further than one or two generations after the monarch and/or the line of succession; or it may be allowed to run into very high numbers, as is often the case in oriental dynasties.

Princes of principalities

Other princes (or the same, see below) derive their title not from their dynastic position as such (which must often be shared with brothers, etc), but from their claim to a unique title of formal princely rank, one named after a specific principality, not after the suzerain/sovereign state, even if they belong to one.

Princes as ruling monarchs

A prince or princess who is the head of state in a monarchy is a reigning prince.

Nominal principalities

If the prince(ss)'s state carries no other specific, formal (rank) title, their domain, typically smaller than a kingdom, is called a "principality".

Generic use

The term "prince" has also been used to describe, in languages like English for lack of a more specific word for this concept, the head of a feudal (vassal) state of lower — generally peerage — rank ruling in his own right, not in a mere gubernatorial capacity; for example, it has been used as a synonym for duke at times.

Princes tasting the throne

Various monarchies provide for different modes in which princes of the dynasty can temporarily of permanently share in the style and/or office of the Monarch, e.g. as Regent of Viceroy (though these offices must not be reserved for members of the ruling dynasty, in some traditions they are, possibly even reflected in the style of the office, e.g. prince-lieutenant in Luxemburg, repeatedly filled by the Crown prince before the grand duke's abdication), or in form of consortium imperii; some have even a practice in which the Monarch can formally abdicate in favor of his Heir, and yet retain a kingly title with executive power, e.g. Maha Upayuvaraja Sanskrit for 'Great Joint King' in Cambodia, though sometimes also conferred on powerful regents who exercised executive powers.

Titular royal princedoms

One type of prince belongs in both the genealogical royalty and the territorial princely styles. A number of nobiliary territories, carrying with them the formal style of prince, are not (or no longer) actual (political, administrative, etc.) principalities, but are maintained as essentially honorary titles (though some land, income etc. may be attached to them), and are awarded traditionally (or occasionally) to princes of the blood, as an appanage.

Titular Princedoms below royalty

In several countries of the European continent, e.g. in France, prince can be an aristocratic title of someone having a high rank of nobility in chief of a geographical place, but no actual princedom, and without any necessary link to Royalty, which makes comparing it with e.g. the British system of "royal" princes difficult.

France

Kings of France started to create aristocrats as princes of someplace from 16th century onwards. The title was placed between marquess and duke in rank (counties were raised to princedoms, then some princedoms to duchies).

Poland

In Poland, the titles of prince dated either to the times before the Union of Lublin or were granted to Polish nobles by foreign kings, as the law in Poland forbade king from dividing nobility by granting them heraditory titles. For more information, see The Princely Houses of Poland.

Russia

In the Russian system, knyaz (translated as "prince"), is the highest degree of nobility, and sometimes, represents a mediatization of an older native dynasty which became subject to the Russian imperial dynasty. Rurikid branches used the knyaz title also after they were succeeded by the Romanovs as the Russian imperial dynasty.

Prince in both meanings in various (western tradition) languages

In each case, the title is followed (when available) by the female form and then (not always available, and obviously rarely applicable to a prince of the blood without a principality) the name of the territorial associated with it, each separated by a slash. If a second title (or set) is also given, then that one is for a Prince of the blood, the first for a principality. Be aware that the absence of a separate title for a prince of the blood may not always mean no such title exists; alternatively, the existence of a word does not imply there is also a reality in the linguistic territory concerned; it may very well be used exclusively to render titles in other languages, regardless whether there is a historical link with any (which often means that linguistic tradition is adopted)

Oriental and other native counterparts

The above is essentially the story of European, Christian dynasties and other nobility, also 'exported' to their colonial and other overseas territories and otherwise adopted by rather westernized societies elsewhere (e.g. Haiti).

Islamic traditions

• Arabian tradition since the caliphate - in several monarchies it remains customary to use the title Sheikh (in itself below princely rank) for all members of the royal family. In families (often reigning dynasties) which claim descent from the prophet Mohammed, this is expressed in either of a number of titles (supposing different exact relations): sayid, sharif; these are retained even when to remote from any line of succession to be a member of any dynasty.

• Malay countries

• In the Ottoman empire, the sovereign of imperial rank (incorrectly known in the west as (Great) sultan) was styled padishah with a host of additional titles, reflecting his claim as political successor to the various conquered states. Princes of the blood, male and female, were given the style sultan (normally reserved for Muslim rulers)

• Persia (Iran) - Princes were referred to by the title Shahzadeh, meaning descendant of the king. Ironically, since the word zadeh could refer to either a male or female descendant, Shahzadeh had the parallel meaning of "princess" as well.

Far East (Confucianist, Hindu, Buddhist, etc)

• China

In ancient China, the title of prince developed from being the highest title of nobility (synonymous with duke) in the Zhou Dynasty, to five grades of princes (not counting the sons and grandsons of the emperor) by the time of the fall of the Qing Dynasty.

Africa

Except for the Arabized, Muslim North and some other monarchies that simply adopted Islamic practices, or in cases where a Western model was copied (e.g. Bokassa I's short-lived Central-African Empire in Napoleonic fashion), usually the styles, or even the systems, are completely independent or almost.

Ecclesiastic and other religious princes

In states with an element of theocracy, this can affect princehood in several ways, such as the style of the ruler (e.g. with a secondary title meaning son or servant of a named divinity), but also the mode of succession (even reincarnation and recognition).

Figurative uses

In Christianity, Jesus Christ is sometimes referred to as the Prince of Peace, and Satan can be called the Prince of Darkness.