Book excerpt: In the first century B.C., Rome was the ruler of a vast empire. Yet at the heart of the Republic was a fatal flaw: a dangerous hostility between the aristocracy and the plebians, each regarding itself as the foundation of Rome's military power. Turning from their foreign enemies, Romans would soon be fighting Romans.Swords Against the Senate describes the first three decades of Rome's century-long civil war that transformed it from a republic to an imperial autocracy, from the Rome of citizen leaders to the Rome of decadent emperor thugs. As the republic came apart amid turmoil, Gaius Marius, the "people's general," rose to despotic power only to be replaced by the brutal dictator Sulla. The Roman army, once invincible against foreign antagonists, became a tool for the powerful, and the Roman Senate its foe.