Plying the Backwaters
The Solomani are humans who claim descent from Earth. When the Solomani first reached the stars, they were shocked to find other humans already there. In a short period of time, the Solomani overwhelmed those humans, and established the Rule of Man (also called the Second Imperium). After several centuries, the Rule of Man collapsed into barbarism and anarchy.
Today, the Solomani control a fairly extensive region of space, but not Earth itself. The Solomani homeworld was captured by the Third Imperium after a brutal war about a century ago. Many Solomani seethe at this, and vow revenge on the Imperium.