The Gallic campaigns firmly established Julius Caesar (100 B.C.--44 B.C.) as one of the greatest commanders of all time. After success there, Caesar turned his loyal army back toward Rome. Crossing the Rubicon, he initiated a civil war, marched triumphally to the capital, besieged Pompey at Brundisium, and pacified Spain. With a tiny army he routed Pompey's far larger forces at Pharsalus, pursued him to his death in Egypt, and established Cleopatra...