The Rellazi Commonwealth was the government of the Rellazi people, located on the planet Rellazus. In 2383, the Commonwealth was led by King Lemus VII Tavli, of the House of Tavli. The King was advised by the Prime Minister of the Rellazi Assembly, who was in turn advised by the Rellazi Ministerial Council. (Star Trek: Remington)
Rellazi law requires military service to succeed to the throne. Lemus was a retired admiral in the Rellazi Home Guard, while his sons Garoz and Datha were both Starfleet officers, and his daughter Jenma was preparing to enter Starfleet Academy as of 2383.