Foreign Prince (prince etrangèr) has been a concept in French royal court of ancien regime. Ancien R gime means Old Regime or Old Order in French; in English, the term refers primarily to the social and political system established in France under the Valois and Bourbon dynasties, and secondarily to any regime which shares the formers defining features: a feudal system under the control...

Those foreign princes, as "foreigners", guests, were not (or were only slightly) subjects of the increasingly autocratic French king. It became the highest form of aristocrat class to be in the court (or in king's service) and however not to be subjugated. Aristocracy is a form of government in which rulership is in the hands of an upper class known as aristocrats. ...

The term prince implies a notion of sovereignty, either actual or potential. As such, it forms a rank that belongs to those who are in line to succeed to a sovereign throne. The French monarchy allowed the rank of a prince to certain scions of foreign reigning houses, who settled in France and were admitted by the French king to his court.

The king was able to display an impression of several nationalities, of a multitude of other rulers, princes, more or less serving him - that is an imperial characteristic: being surrounded and supported by many many "client kings". Imperial is a term that is used to describe something that relates to an Empire, Emperor, or the concept of Imperialism. ...

Those foreign princes were not subject to being required to do such obeisances to the monarch that were due from his own subjects. A coveted privilege was to be entitled to have a seat when in company of royal personages of France itself. Anecdotally: apparently, standing on their own feet was not the all-time favorite for these worthies.

The other side of this bunch of privilegization was that the French without this privilege became yet more "enslaved" in an increasingly autocratic and centrally-governed kingdom, as there was this way for most important people to escape several excesses and stupidities of government power, and thus they did not feel the same pressure to resist the growth of arbitrary royal power.

Examples: The de La Tremoille, princes of Naples; Prince of Dombes; the de Longueville, princes of Neuchatel; the de Savoie of several branches (Carignan, Nemours).

Examples include also the prince of Orange and the prince of Monaco (whose sovereignties were both recognized in the 15th century), and most proliferatingly, a bunch of dynasts of the House of Lorraine (Mercoeur and Guise). Prince of Orange is a title of nobility, originally associated with the principality of Orange in southern France. ... Prince(ss) of Monaco is a title given to certain members of the princely family of Monaco. ... The Duchy of Lorraine was an independent state for most of the period of time between 843 to 1739. ... Guise is a commune of the Aisne département in northern France. ...

Louis XIV started to allow also French families to the privilege of "foreign reigning house" in cases they held claims to foreign sovereignties, however doubtful the claim. Examples include the de La Tour d'Auvergne (as heirs of sovereign dukes in Lower Lorraine), and the de Rohan family (as heirs of the eldest line of the house of Montfort that ruled Brittany). The Duchy of Lower Lorraine or Lower Lotharingia encompassed part of modern-day Belgium, the Netherlands, Germany west of the Rhine, and a part of northern France (east of the Schelde). ... Traditional coat of arms Modern flag (Gwenn-ha-du) Historical province of Brittany région of Bretagne, see Bretagne. ...

In 18th century some titles of prince of the Holy German Empire or the Papacy were recognized in France (Broglie, Polignac), even though they did not correspond to actual sovereignty. Arms of the ducs de Broglie (or, a saltire anchory azure) The title of Duc de Broglie was a French peerage belonging to a family of Piedmontese origin, which emigrated to France in the year 1643. ... Polignac is a French card game for four players. ...

These princedoms were not created, at least not by the French monarchy, but they were "recognized". (Even naturalization is too strong a term to be used in these cases, as the recognition did not confer any French fiefdom or peerage right, but only recognized recipients of cordial treatment accorded to dignitaries of other realms.) Naturalization is the act whereby a person voluntarily and actively acquires a nationality which is not his or her nationality at birth. ...

Recognition to the class of foreign princes was somewhat dependent on royal favor. Quite dubious princely families were accepted over time.

Many important French personages came thus to enjoy the exemptions and privileges that were allowed to foreign princes.

Foreign princes were entitled to style "haut et puissant Prince" (high and mighty prince) in the French etiquette.

• Francois Velde, a chapter on princes etrangeres [1] at Heraldics