The Saga of Seven Suns #3: Horizon Storms by Kevin J. Anderson

The titanic war between the Hydrogues and Faeros continues to sweep across the Spiral Arm, extinguishing suns and destroying planets. Chairman Wenceslas and King Peter must now unify the human race with iron-fisted policies in a final bid to stand together — or face total annihilation. But disparate civilizations are forging new alliances that threaten the old order. The Roamer and Theroc clans will not yield their independence, and the alien leader Jora’h now faces a threat no other Mage-Imperator has ever seen — an astonishing civil war among the Ildirans that could break apart the entire Empire.