Translation guide
A territory ruled by a prince or princess; the rank or office of a prince.
The learner wants to refer to a principality as a political or geographical entity, such as Monaco or historical principalities.
Standard term for a principality as a sovereign state or territory ruled by a prince. Used for modern examples like Monaco (モナコ公国) and historical ones.
Also means principality, but specifically for a territory ruled by a marquis or prince of lower rank. Less common than 公国 and often historical.
The learner wants to refer to the abstract status, dignity, or position of being a prince, not the territory.
Means 'the rank/position of a prince'. A natural way to express the abstract concept.
The English word 'principality' is sometimes confused with 'principle'. In Japanese, 'principle' is 原理 (げんり) or 原則 (げんそく). Make sure the context is about a prince's domain or rank.
モナコは小さな公国です。
Monaco is a small principality.
There were many principalities in medieval Europe.
その侯国は神聖ローマ帝国の一部だった。
That principality was part of the Holy Roman Empire.
He assumed the rank of a prince.
Specifically 'the rank of a duke', but can be used when principality refers to a prince's title in a broader sense. Note: 公爵 is duke, not prince, but in some contexts principality may be rendered this way.
The principality was hereditary.