The Alliance Fleet, also called the Rebel Fleet, referred to the various spacecraft operated jointly by the Rebel Alliance in their struggle against the Galactic Empire. Although it was minuscule in size compared to the Imperial Navy, and in many cases its ships were of non-military design, the fleet proved to be a thorn in the Empire’s side throughout the Galactic Civil War.
Following the Battle of Endor and the creation of the New Republic, the Rebel fleet was renamed into the New Republic Defense Fleet.
The fleet was controlled under the auspices of Fleet Command, the branch of the Alliance military that oversaw all fleet operations. Fleet Command was headed by the admiral of the fleet, which was Ackbar for the entire history of the Rebellion. While Ackbar was head of the fleet, he was assisted in command by a series of line admirals, who each were responsible for components of the fleet. Due to the importance of the fleet to the Alliance, Fleet Command was considered one of the most important Supreme Allied Commands.
When the Alliance became the New Republic, the Rebel Alliance Fleet became the New Republic Defense Fleet. Also under the New Republic military structure, starfighters were under Starfighter Command.