The Soldiers of the One (also referred to as "STO") is an extremist religious group advocating the worship of a single all-powerful god.
The Soldiers of the One (STO) has been inactive for ten years. What they did prior to this and during the dormant time is currently a mystery. ("Reins of a Waterfall")
Agent Jordan Duram investigates a train bombing, which he believes is an act of terrorism by the STO. He also believes that Ben Stark and Zoe Graystone were involved in this group. The train bombing is actually a suicide bombing by Ben Stark. Whether or not Zoe was complicit or agreed with this act is uncertain. The amount to which the STO are involved is also uncertain. ("Pilot")
The train bombing affects both the Graystone and Adama families in particular. Joseph Adama attends a briefing (where those affected by the bombing are informed) that the STO is most likely behind this attack. However, as soon as this is revealed to the audience, Joseph leaves. ("Pilot")
The internal structure and exact nature of the STO is also unknown at this point.
The STO symbolEdit
The symbol of the STO is identifiable with the symbol of infinity, however it is notable that, according to the re-imagined mythos, that our modern day Earth occurs approximately 150,000 years or more after the events in Caprica. How the symbol of the STO and the infinity symbol on modern day Earth are related is unsure. However, if we assume that the STO are actually being communicated to by the same god that Baltar preaches in the Battlestar Galactica re-imagined series, a force of nature that exists within the show, then it is possible this symbol is important to the entity of god, and will likely arise in any society that god deems important to communicate with.
The STO-infinity symbol is used by Zoe at one point in the pilot to access the V-Club, like a passcode. She enters into a secret room within the V-Club by activating a sensor that is in the shape of the STO-infinity symbol. Whether or not the V-Club and the STO are related is uncertain at this point.
1 "New Video Clips from Caprica" on The Caprica Times