He was the leader of a religious faction, who believe that their planet's Stargate was a ring built by the "gods." However, his interpretation of the "gods" was proven to be false. After SG-1 activated Tegalus' Stargate in 2004, Soren heard of the event and claimed that it had proven his theory of what the Gate does, and took that as a sign that the "gods" will return again soon. He took his extremist group and stormed all of the Rand Protectorate's military installations, in the hopes of wiping out the neighboring nation, the Caledonian Federation. His group managed to have overwhelmed the installations, and succeeded in taking over the planet's underground bunker. He had Commander Gareth and anyone who followed him killed. His coup d'etat was successful, and he ruled Rand, renaming it "Avidan", which means "the gods are just" in an ancient Goa'uld dialect.
Over the next few weeks, his men insisted that the people will live in peace, despite the lack of basic supplies to keep the Tegalans alive. After Dr. Daniel Jackson was trapped on the planet, since Soren's people guarded the Gate, SG-1 tried to find him, but Soren wouldn't allow it, claiming that their presence will scare the people. SG-1 agreed to invite him to Stargate Command, with the promise of giving his people medical supplies to stave off illnesses. However, he refused, but says that the Tau'ri's weapon technologies would be useful, despite wanting to live in peace. After he left, SG-1 thought that the only way to rescue Jackson and save the Tegalans would be to stop Soren.
They succeeded in contacting Jackson, and with the help of Jared Kane succeeded in taking over the bunker, and had Soren surrounded. He showed himself, and got his hands up. However, since he killed Gareth, Rand's leader, he committed treason. Kane paid no attention to his surrendering, so he raised his rifle, and shot Soren dead. Jackson told Kane that they hoped that he didn't make him a martyr, because of his influence among the Tegalans. (SG1: "Icon")