List of current sovereign monarchs

A monarch is the head of a monarchy, a form of government in which a state or polity is ruled by an individual who normally rules for life or until abdication, and typically inherits the throne by birth. Monarchs may be (as in all absolute monarchies) or may be ceremonial figureheads, exercising only limited or no reserve powers at all, with actual authority vested in a legislature and/or executive cabinet (as in many constitutional monarchies). In many cases, a monarch will also be linked with a state religion. Most states only have a single monarch at any given time, although a regent may rule when the monarch is a minor, not present, or otherwise incapable of ruling. Cases in which two monarchs rule simultaneously over a single state, as is the current situation in Andorra, are known as coregencies.

Monarchs are distinguished by their titles and styles, which in most cases are defined by tradition, and guaranteed under the state's constitution. A variety of titles are applied in English; for example, "king" and "queen", "prince" and "princess", "emperor" and "empress". Although they will be addressed differently in their local languages, the names and titles in the list below have been styled using the common English equivalent. Roman numerals, used to distinguish related rulers with the same name, have been applied where typical.

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