* Bahrain: A hereditary monarchy ruled by the Al Khalifa family.
* Liechtenstein: A hereditary monarchy ruled by the House of Liechtenstein.
* Monaco: A hereditary monarchy ruled by the Grimaldi family.
* San Marino: Two Captains Regent, each elected for a six-month term.
* Vatican City: An absolute monarchy led by the Pope.
Formerly independent states under one ruler:
* Austria-Hungary (1867-1918): A dual monarchy under Emperor Franz Joseph I.
* Ottoman Empire (1299-1922): A caliphate and empire ruled by the Ottoman sultans.
* Russian Empire (1721-1917): An empire ruled by the Romanov dynasty.
* German Empire (1871-1918): A monarchy under Emperor Wilhelm II.
* Qing Dynasty (1644-1912): A dynasty that ruled over China.