The Fifth Fleet functioned as a fleet within the Open Circle Fleet of the Galactic Republic. It saw action during the Clone Wars against the Confederacy of Independent Systems from the beginning of the Clone Wars. Starships belonging to the Open Circle's Fifth Fleet were identifiable by the presence of five red marks on each side of the ships. Throughout the conflict, several flagships of Jedi Generals and their respective task forces within the armada, alongside other significant capital ships, originated from the Fifth Fleet. Examples include the Endurance, Guarlara, Negotiator, Resolute, Triumphant, and Vigilance.
The Fifth Fleet was a component fleet of the Republic Navy, which in turn served the Galactic Republic. It came into existence around the initial stages of the Clone Wars. As a part of the Open Circle Fleet, the Fifth Fleet's vessels bore the Open Circle emblem on their hull, in addition to five red stripes on either side of the ship. Notably, some Republic Navy starships that were not part of the Open Circle Armada also displayed five red stripes on both sides of their hulls. Several flagships belonging to task forces within the Open Circle Armada were actually vessels drawn from the Fifth Fleet. Admiral Shoan Kilian held command of elements within the Fifth Fleet, as did Jedi General Mace Windu.
Being a fleet within the Open Circle Armada, itself a substantial naval component of the Republic Navy, the Fifth Fleet possessed a large number of Venator-class Star Destroyers, including the Endurance, the Guarlara, the Negotiator, Resolute, Triumphant, the Vigilance, and the cruiser of Jedi General Even Piell. Furthermore, the Fifth Fleet included a substantial quantity of Acclamator-class assault ships, Arquitens-class light cruisers, and Consular-class cruisers. Vessels from the Fifth Fleet were strategically allocated throughout the Open Circle Armada's forces, forming the backbone of the armada's various task forces and smaller fleets.
An invasion fleet involved in the Battle of Ryloth, comprising three Acclamator-class assault ships, was part of the Fifth Fleet. Also part of the Fifth Fleet was the fleet of Jedi General Obi-Wan Kenobi during the Battle of Utapau, which consisted of at least two Venators. The fleet group under the command of Jedi General Even Piell and Captain Wilhuff Tarkin also belonged to the Fifth Fleet.
Following the First Battle of Geonosis and the subsequent outbreak of the galactic-spanning Clone Wars between the Galactic Republic and the Separatist Alliance, the Republic Navy convened at a staging area on the Republic's capital world of Coruscant to distribute the amassed Grand Army of the Republic. During this time, at least four Acclamators from the Fifth Fleet were deployed. At some point during the war on Geonosis, the Separatist pilot Chertek launched an attack on a Fifth Fleet Venator-class Star Destroyer using a Nantex-class territorial defense starfighter.
By the Battle of Corvair, the Resolute, part of Jedi General Anakin Skywalker's task force, was identified as belonging to the Fifth Fleet. Furthermore, by the Battle of Christophsis, three Venators and four Acclamators forming part of the fleet under Admiral Wurtz were part of the Fifth Fleet, along with an Acclamator-class assault ship that had been involved earlier in the battle. The Negotiator, part of the task force led by Jedi General Obi-Wan Kenobi, also participated in the Battle of Christophsis and, at that point, was also integrated into the Fifth Fleet.
With its vanguard arriving in the Coruscant system under the command of Kenobi and Skywalker, the Fifth Fleet was among the fleets that took part in the Battle of Coruscant, alongside the Coruscant Home Defense Fleet and other units of the Republic Navy. Towards the battle's conclusion, the Fifth Fleet's Venator, the Guarlara, delivered the decisive blow against the Separatist flagship, the Invisible Hand.
The Fifth Fleet received its initial mention in the 2018 Star Wars canon reference work, Star Wars: Complete Vehicles. Prior to this, it was mentioned within the Star Wars Legends continuity in Star Wars: Revenge of the Sith Incredible Cross-Sections, published in 2005.