The Battle of Dakara was a battle the newly Free Jaffa Nation waged against the Goa'uld Empire led by the System Lord Ba'al which later turned into a battle between the Replicators and Goa'uld Empire and the Free Jaffa, which ultimately resulted in the extinction of the Replicators and the major fragmentation of the Goa'uld Empire.
With the Replicator invasion of the Milky Way, the Replicators quickly eliminated the remaining System Lords, allowing Ba'al to absorb their forces to launch a combined offensive. Many of the Jaffa abandoned the rebel cause, believing the Replicators to be an evil plague to punish them for being disobedient. To utterly destroy the Goa'uld's image as gods, Teal'c advocated that the remaining Rebel Jaffa take Dakara, the place where Jaffa were first made slaves to the Goa'uld.
Once the Rebels had taken Dakara, the Rebels then began forming what would become the Free Jaffa Nation. Meanwhile Ba'al, under the orders of Anubis, was dispatched to retake it, hoping to take the Dakara superweapon. Ba'al, fearing for his life, warned Brigadier General Jack O'Neill about the threat. Replicator Carter, after probing Dr. Daniel Jackson's mind, also learned of the threat, and dispatched her brethren to destroy it. (SG1: "Reckoning, Part 1")
The Free Jaffa engaged Ba'al's much larger fleet when it arrived. The Free Jaffa divided the Goa'uld Empire forces, and began a strategic retreat to draw Ba'al away from Dakara. Ba'al followed knowing they wanted him to follow, and hoped that SG-1 would destroy the device. Lt. Colonel Samantha Carter and Jacob Carter were eventually able to locate the device, but Selmak realized that the device worked on principles similar to the Replicator disruptor. Carter was able to interface with the device, but realized that they would have to hit every Replicator at once to completely destroy them. Unable to reprogram the Stargate to dial every address, they turned to Ba'al for help. Ba'al agreed, and a surprising ceasefire between the Free Jaffa and the Goa'uld fleet was declared. Nerus was able to devise a way to dial every gate.
As they modified the energy output, the Replicator fleet arrived in force, attacking Dakara. The Free Jaffa and Goa'uld fleet engaged the Replicators, hoping to buy Carter and Jacob enough time to activate the weapon. On the ground of Dakara, a Replicator Ship landed and began pouring out Replicators, which the Jaffa used FN P90 Personal Defense Weapons to repel. Dr. Daniel Jackson, still being probed by Replicator Carter, took control of the Replicators long enough to allow Jacob to activate the device. The Stargate dialed every address possible, and the Dakara superweapon appeared from out of the mountain where it was hidden under and released an energy wave that traveled through the Gate and spread beyond the planet as well, destroying all Replicators, including Replicator Carter who recently killed Daniel. Ba'al ordered the previously Replicator controlled Ha'taks to be reclaimed, but Bra'tac and a group of Free Jaffa were able to board Ba'al's flagship, killing his Kull guards and aimed at Ba'al, but he activated an Asgard transporter and fled, which concluded the battle. (SG1: "Reckoning, Part 2")
With the flight of Ba'al, the Goa'uld's image as gods was utterly destroyed. The Jaffa began rebelling en masse, heading to Dakara to pledge allegiance to the new Free Jaffa Nation. Anubis later attempted to use the weapon to destroy all life in the galaxy so that he could rebuild the galaxy in his own image but Dr. Daniel Jackson, who had been killed in the battle by Replicator Carter convinced Oma Desala to stop him and Daniel was resurrected by The Others. Thus ending the Tau'ri-Goa'uld war.(SG1: "Threads")
With the defeat of the Goa'uld Empire after the supposed death of Anubis, SG-1 disbanded itself: Jack O'Neill was promoted to Major General and named commander of Homeworld Security, Lt. Colonel Samantha Carter became head of Stargate Command's R&D section at Area 51, Teal'c went to Dakara to help build the new Jaffa government, and Dr. Daniel Jackson intended to join the Atlantis expedition. Lt. Colonel Cameron Mitchell later brought Daniel, Sam and Teal'c back together to reunite SG-1, which Vala Mal Doran later joined albeit on a temporary basis. (SG1: "Avalon, Part 1", "Ex Deus Machina")
But the Goa'uld Empire itself would not be totally defeated as the only System Lord left Ba'al who retook control of some of the remaining Goa'uld fleet and a brainwashed loyalists Jaffa army as well as a dozen strongholds who led a post-war campaign, he was finally killed by the Colonel Cameron Mitchell from an alternate timeline in 1939 when he tried to change history over three years after the battle. His last remaining clone had its symbiote extracted by the Tok'ra and while the symbiote died, his host Aziru survived. (Stargate: Continuum)