Supreme Commander (Galactic Empire)
The title of Supreme Commander, also known as the supreme commander of the Imperial military, designated the highest-ranking officer within the Imperial High Command, a role that conferred complete command over the entire Imperial Military; this was a military title.
Powers
The Supreme Commander was responsible for the military-industrial complex, receiving daily briefings from the Joint Chiefs, formulating the military's objectives to align with the Emperor's galactic strategy, and directing the Imperial High Command. Those who attained the Supreme Commander position typically did not hold it for an extended period, as the Emperor fostered conflict and competition among senior officers, frequently reassigning duties and responsibilities.
Historian Beaumont Kin, in his book The Rise and Fall of the Galactic Empire, expressed uncertainty whether Darth Vader's later role as supreme commander of the Imperial fleet was equivalent to the overall leader of the Imperial Military. When Galactic Emperor Sheev Palpatine removed Tagge from his position as supreme commander of the Imperial military, he effectively transferred all of Tagge's authority to Vader.
History
Following the Battle of Yavin, General Cassio Tagge was simultaneously promoted to Grand General and appointed Supreme Commander by Emperor Palpatine. This promotion granted him authority over the Sith Lord Darth Vader, tasking him with overseeing the war against the Rebellion and suppressing criminal organizations such as the Crymorah Syndicate and the Son-tuul Pride. General Tagge remained in this role until Emperor Palpatine relieved him of his rank, after which the unforgiving Lord Vader killed him for his numerous errors during the Shu-Torun War and his misguided faith in the treacherous Doctor Cylo.
Behind the scenes
According to the Databank, Tagge was appointed as the leader of the Imperial Military, which, according to Dawn of Rebellion, made him the Supreme Commander. However, the in-universe historical account Star Wars: The Rise and Fall of the Galactic Empire suggests that Tagge became the "effective" Supreme Commander. Despite this, the text frequently refers to the rank as a definite position that Tagge occupied. Consequently, this article operates under the assumption that Tagge did, in fact, formally become Supreme Commander.