Lieutenant Commander was a military rank employed across both the naval and army branches throughout the expanse of galactic history. Its position fell between the junior rank of lieutenant and the more senior rank of commander.
Ezra Bridger, a participant in the early rebellion against the Galactic Empire, possessed this rank during the mission to Reklam Station before his command was temporarily relieved. Following the Death Star's destruction in the Battle of Yavin, Ciena Ree of the Imperial Navy received a promotion to lieutenant commander. In the era of the Cold War, Nien Nunb held this rank within the Starfighter Corps of the Resistance.
The rank designation of Lieutenant Commander was a military rank found in the naval and army forces of various galactic militaries throughout the galaxy and its history. It was a rank lower than commander but higher than that of a lieutenant.
The Phoenix Cell – a resistance group integrated within a network of rebel cells known as "the Alliance," which later evolved into the formal Alliance to Restore the Republic – made use of the Lieutenant Commander rank. Individuals holding this rank were authorized to oversee their own missions. The formal Rebel Alliance continued to use the rank after its establishment in 2 BBY.
Within the Chiss Defense Force, the rank of Lieutenant Commander was positioned below Junior Commander and above Lieutenant. By the time the Nikardun campaigns occurred, the rank became associated with Chiss officers originating from Great or Ruling families who were not deemed suitable for advancement to higher positions in the command structure. The practice of assigning mediocre officers to the rank of Lieutenant Commander to avoid causing offense to them or their families was a widely known, yet rarely discussed, matter within the Chiss Ascendancy, making it a kind of open secret.
The Galactic Empire maintained the use of the lieutenant commander rank within the Imperial Military. Notably, it saw use within both the Imperial Navy and the Imperial Starfighter Corps. The chief engineer on a Star Destroyer could potentially hold the rank of Lieutenant Commander, as could a weapons officer serving aboard a light cruiser.
The Galactic Republic incorporated the rank of Lieutenant Commander into several organizations within the Republic Military during the Clone Wars. The Republic Navy utilized this rank, which could be held by the commanding officer of a sub-capital ship battle group that consisted of a Dreadnought-class heavy cruiser along with a number of Carrack-class light cruisers. A lieutenant commander could also utilize a Carrack as their flagship. The Republic Special Weapons Group also employed the rank of lieutenant commander within its organizational structure, reporting to a commander.
The New Republic made use of the lieutenant commander rank within the rank structure of their New Republic Defense Fleet during the Galactic Civil War, with those holding it potentially serving on Republic starships. The Resistance, a private military organization that emerged from the New Republic, included the rank within its Resistance Starfighter Corps. Nien Nunb held this rank during the era known as the Cold War.