Records of heads of state

Heads of state throughout the world and at all periods of history may be ranked according to characteristics such as length of time holding that position; age of accession or death; or physical attributes. In this way world records in these characteristics may be identified, although the historical basis for such claims is frequently uncertain.

The longest-reigning male monarch ever known is disputed between the following candidates:

The longest undisputed reigning male monarch known is Sobhuza II, who ruled the Kingdom of Swaziland as a absolute monarch under the title of Paramount Chief of Swaziland and later King of Swaziland. He ruled for 82 years, 8 months, 11 days.

The longest current reigning male monarch is Hassanal Bolkiah, who is currently the Sultan and Yang di-Pertuan of Brunei ("(he) who is Lord"), a absolute monarch of the Nation of Brunei, the Abode of Peace.

The longest current reigning constitutional male monarch is Carl XVI Gustaf of Sweden, who is currently the King of Sweden of the Kingdom of Sweden.

The longest reigning female monarch ever known was Eleanor of Aquitaine, who ruled the Duchy of Aquitaine as a feudal absolute monarch under the title of Duchess of Aquitaine. She ruled for 66 years, 11 months, and 23 days.

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