The Defiance Task Force, sometimes known as Defiance Group, was a task force of the Alliance to Restore the Republic under the command of Admiral Nammo. It was named after Nammo's command ship, the Defiance.
In addition to the MC80 Star Cruiser Defiance, the Defiance Task Force included the MC40a light cruiser Valiant, the Nebulon-B escort frigates Jericho and Valiance, the DP20 frigate Spear, the CR90 corvettes Lance and Masanya, and the GR-75 medium transports Tuima, ATS-0014, ATS-0021, ATS-0022, ATS-0121, ATS-0157 and ATS-0416.
The task force accompanied the Defiance throughout much of her operational history with the Rebellion, certainly between the Battle of Hoth and the Battle of Endor. Shortly following the Alliance's infamous defeat at Hoth, the task force was trapped in the Anoat sector, with the Imperial Corrupter Task Force pursuing them.
After a brief campaign to weaken the Imperial influence in the sector, and their security measures, the task force was able to escape, thanks in part to the efforts of Rebel pilot Ace Azzameen.
After their escape, the task force was drastically reorganized. This new group joined up with the rest of the Rebel fleet at Sullust, prior to the Battle of Endor. En route, however, the task force came under attack from an Imperial task group, comprising the Nexus, the Xerxes and the VSD Vagrant. The Defiances starfighter squadrons, along with escorts Olin Garn and Ace Azzameen, hindered the Imperial efforts to destroy the vessels, and the task force made it to Sullust. It is unknown what happened to the original Defiance Task Force, though the Jericho later served alongside the Liberty.