Citadel Fleet
From Mass Effect Wiki
The exact number of ships in the Council's fleets is unknown, but there were enough vessels to patrol every mass relay linking Citadel space to the Terminus Systems and still leave enough stationed with the Citadel Fleet to protect the station. Ambassador Udina claimed that the Citadel Fleet was large enough to secure the entire Attican Traverse if the Council wished.
In the aftermath of the battle on Virmire, the Council deployed its fleet to every relay in Citadel space, believing that Saren Arterius wouldn't dare attack the Citadel. However, the massive dreadnought Sovereign, launched a surprise attack against the Citadel. During the attack, the Destiny Ascension ordered Citadel control to close the station's Wards, creating an impenetrable fortress. However, Saren had used the Conduit to infiltrate the Citadel and shut down both the Citadel and the mass relay network, subjecting the fleet to the full force of the geth attack and preventing any reinforcements from arriving. Sovereign then broke through the fleet and closed the Citadel's Ward arms behind it.
The Destiny Ascension managed to evacuate the Citadel Council but was unable to fight her way through the hordes of geth ships accompanying Sovereign. Commander Shepard eventually reactivated the mass relays, allowing the Alliance Navy and the Normandy to aid what was left of the Citadel Fleet. It was then up to Shepard to decide whether to have the reinforcements save the Council and the Destiny Ascension, or to let them die while they waited for the Ward arms to reopen.
[edit] Aftermath
The fate of the Citadel Fleet depends on the player's Paragon or Renegade choice. If Shepard chooses to save the Council, at least the flagship Destiny Ascension survives. It is not known how much of the rest of the fleet survived.
If Shepard lets the Council die, it is implied that most of the fleet is destroyed. However, it is important to note that the Citadel Fleet is only that portion of the Council's forces actually stationed at the Citadel. Most Council-aligned forces would be stationed or patrolling throughout the vast area of space the Council controls.
[edit] Trivia
In Mass Effect: Ascension it is stated that the greater part of the Citadel Fleet is destroyed in the attack on the Citadel, leaving the Alliance Navy as the dominant military power in Citadel space (pg 4). Given the scope of the Citadel Fleet, its deployment across the galaxy to defend the mass relays at the time of the attack, and the fact it is composed of vessels from several powerful races, the veracity of this statement is uncertain.
