Prince regnant

A prince is a male ruler or member of a monarch's or former monarch's family. Prince is also a title of nobility, often hereditary, in some European states. The feminine equivalent is a princess. The English word derives, via the French word prince, from the Latin noun princeps, from primus (first) + capio (to seize), meaning "the chief, most distinguished, ruler, prince".

The Latin word prīnceps (older Latin *prīsmo-kaps, literally "the one who takes the first [place/position]"), became the usual title of the informal leader of the Roman senate some centuries before the transition to empire, the princeps senatus.

Emperor Augustus established the formal position of monarch on the 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 the country or attending religious rituals, and, for that task, granted them the title of princeps.

The title has generic and substantive meanings:

The original, but now less common use of the word, originated in the application of the Latin word princeps, from late Roman law, and the classical system of government that eventually gave way to the European feudal society. In this sense, a prince is a ruler of a territory which is sovereign, or quasi-sovereign, i.e., exercising substantial (though not all) prerogatives associated with monarchs of independent nations, as was common, for instance, within the historical boundaries of the Holy Roman Empire. In medieval and Early Modern Europe, there were as many as two hundred such territories, especially in Italy, Germany, and Gaelic Ireland. In this sense, "prince" is used of any and all rulers, regardless of actual title or precise rank. This is the Renaissance use of the term found in Niccolò Machiavelli's famous work, Il Principe.

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