A Lyran duke was a Lyran noble, higher than a Lyran count and second only to the King-Emperor of the Lyran Star Empire in both civilian and military hierarchy. They were militarily equivalent to a fleet admiral. They ruled over five counties, only one of which he controlled directly, as the control of the other four was delegated to counts. In the 23rd century, there were four dukes, but due to the expansion of the Lyran Star Empire in the 24th century, eight dukes rivaled one another. They operated the major shipyards and starbases. (RIS Bouteina: "Battle at the Grave of Thoughts")