Captain of the Guard, also rendered as captain of the guard, was a designation given to the captain heading the Black Sun Guard, the Zygerrian Royal Guard's captain, and the Senate Guard of the Galactic Republic.
Lang, a mercenary, held the position of Captain of the Guard within Magistrate Morgan Elsbeth's army, leading the defenses for the fortified city of Corvus.
Enoch, the Night Trooper captain, acted as Captain of the Guard circa 9 ABY on the Imperial Grand Admiral Mitth'raw'nuruodo's primary vessel, the Chimaera, following its unexpected displacement to a distant galaxy via a group of purrgil led by Ezra Bridger.
On a starship belonging to the First Order Navy, stormtroopers were ultimately under the command of a captain of the guard. However, in the event of an alert, stormtroopers were required to obey orders from any officer, irrespective of their military affiliation.