Regent of the Klingon Empire

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In the Mirror Universe, the Regent of the Klingon Empire was the Klingon head of state and head of government. (DS9 episodes: "Shattered Mirror", "The Emperor's New Cloak")

The Regent was considered to hold the throne for Kahless the Unforgettable until his return. The Regent, therefore, often received the full title, "His Imperial Majesty, He Who Holds the Throne for Him Who Shall Return." (TOS - Mirror Universe novel: The Sorrows of Empire)

From the 2260s to 2288, the Regent of the Klingon Empire was Sturka. That year, he was slain by Gorkon, Son of Toq, who later formed the Klingon-Cardassian Alliance and defeated the Terran Republic, executing Consul Spock in the former Terran imperial palace. (TOS - Mirror Universe novel: The Sorrows of Empire)

Regents of the Klingon Empire
	Sturka • Gorkon, Son of Toq • Worf, Son of Mogh • Martok, Son of Urthog

Heads of Government
Interstellar States	Federation President • Klingon Chancellor • Romulan Praetor • Imperial Romulan State Empress • Cardassian Castellan • Cardassian Chief Executor • Ferengi Grand Nagus • Tzenkethi Autarch • Gorn Imperator • Breen Domo • Orion Chancellor • Tholian Ruling Conclave • Thallonian Prime Minister • Tezwan Prime Minister • Enoch President • Kropasar High Cyning • Caeliar Tanwa-Seynorral
Federation Member States	United Earth Prime Minister • Vulcan Administrator • Vulcan High Command Administrator • Andorian Chancellor • Alpha Centauri Governor • Bajoran First Minister • Trill President • Cestus Governor • Betazoid Governor • Denevan President • Pacifican Governor • Peliar Zel Governor • Zaldan Leader
Federation Colonies	Tarsus Governor • Alpha V Governor • Mantilles Governor • Caldos Governor
UFP Member State Polities	United States President (United Earth) • Governor of Prophet's Landing (Republic of Bajor)
Mirror Universe	Terran Emperor • Terran Consul • Klingon Regent