Monarchy of Liechtenstein

Sovereign Prince of Liechtenstein
Incumbent
Hans-Adam II since 13 November 1989
Details
Style	His Serene Highness
Heir apparent	Alois, Hereditary Prince of Liechtenstein
First monarch	Karl I, Prince of Liechtenstein
Formation	1608
Residence	Vaduz Castle

The Sovereign Prince (Fürst) of Liechtenstein is the monarch and head of state of Liechtenstein. The Princely Family of Liechtenstein, after which the sovereign principality was named in 1719, hails from Castle Liechtenstein in Lower Austria, which the family possessed from at least 1140 to the thirteenth century, and from 1807 onward. It is the only remaining European monarchy that practises strict agnatic primogeniture, meaning only first-born males may inherit the throne.

Through the centuries, the dynasty acquired vast swathes of land, predominantly in Moravia, Lower Austria, Silesia, and Styria, though in all cases, these territories were held in fief under other more senior feudal lords, particularly under various lines of the Habsburg family, to whom several Liechtenstein princes served as close advisors.

Without any territory held "immediately" (i.e., directly) from the Imperial crown, the Liechtenstein family, although noble, did not qualify for a seat in the Diet of the Holy Roman Empire. By purchase in 1699 and 1712 from the Counts of Waldburg-Zeil-Hohenem of, respectively, the small Herrschaft (lordship) of Schellenberg and the countship of Vaduz, the Liechtensteins acquired immediate lands within the Holy Roman Empire which made them eligible for elevation to the Imperial Diet. Thereby, on 23 January 1719 Emperor Charles VI decreed Vaduz and Schellenberg were henceforth united and raised to the status of a Fürstentum (principality) under the name "Liechtenstein" for "[his] true servant, Anton Florian von Liechtenstein".

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Wikipedia