Duchy Versus Dukedom
A duchy is the territory or geopolitical entity ruled by a duke. The term implies a territorial domain, within which the duke has actual subjects or significant land holdings, with respect to which the duke has or had unique legal privileges, e.g. sovereignty or manorial rights or entitlement to certain duties or income from residents (e.g. the corvée), etc. A dukedom is the title or status of a duke, a rank in the present or past nobility, and is not necessarily attached to a duchy. A few examples exist today: The Grand Duchy of Luxembourg is a fully independent state and its head, the Grand Duke, is a sovereign monarch ruling over his Luxembourgeois subjects. The Duke of Cornwall holds both the dukedom (title) and Duchy (estate holdings), the latter being the source of his personal income; whilst the Duke takes his Sovereign rights from Cornwall, those living in his estates are currently subjects of the British Sovereign. In Scotland the same person is always the Duke of Rothesay as well, but this is a dukedom (title) without a duchy (territorial ownership). Similarly, the British Sovereign rules and owns the Duchy of Lancaster as both Sovereign and Duke of Lancaster, with the income of the duchy estates providing the Sovereign's Privy Purse. He or she also rules the Channel Islands as Sovereign and Duke of Normandy, but without especial income from them.
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