THE SECOND FLEET
The Second Fleet was a Federation Alliance Fleet that participated in the Dominion War.
During the second Battle of Deep Space 9, in late 2373, the Second Fleet task force crossed the border into Cardassian space and destroyed the Dominion shipyards on Torros III. The fleet was later joined by the USS Defiant and IKS Rotarran following the evacuation of Deep Space 9. At that time, the Second Fleet's task force was a comprised of Galaxy-class, Defiant-class, Miranda-class, Excelsior-class, Saber-class, Akira-class and Steamrunner-class Federation starships, as well as Vor'cha-class, K'vort-class, and K't'inga-class Klingon starships. (DS9: "Call to Arms")
In early 2374, after three months of relentless battles of engaging and retreating from the Jem'Hadar, the Second Fleet was reduced to a third of its original size. Of the ships to survive, including the Defiant and Rotarran, were the USS Elkins, USS Fredrickson, USS Raging Queen and USS Curry. (DS9: "A Time to Stand")
Later in 2374, Benjamin Sisko developed a counterattack against the Dominion, in hopes of recapturing Deep Space 9, by putting together a large task force comprised of elements of the Second, Fifth, and Ninth Fleets.
Once Sisko was given the "go ahead" from Starfleet Command, the Second Fleet was ordered to fall back past the Kotanka system and regroup at Starbase 375. This strategy was cause for concern to those in the Dominion watching Federation fleet movements, including Damar and Weyoun. (DS9: "Favor the Bold")
The combined fleet later encountered a Dominion fleet in a successful engagement, in a region of space between Deep Space 9 and Starbase 375. Among the ships in this combined fleet were the USS Centaur, USS Cortez, USS Galaxy, USS Hood, USS Magellan, USS Majestic, USS Sarek, USS Sitak, and USS Venture. (DS9: "Sacrifice of Angels")
The Second Fleet was later responsible for striking against the occupying Dominion forces on Betazed three times in a period of a month. They continued to fortify their position, and brought in reinforcements to their positions on the surface. (DS9: "The Sound of Her Voice")